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LIPPINCOTT 
FARM  MANUALS 


^ 


'  The  first  farmer  was  the  first  man,  and  all  historic 
nobility  rests  on  possession  and  use  of  land.  ' 

— Emerson. 


LIPPINCOTT'S 

FARM  MANUALS 

EDITED    BY 

KARY  C.  DAVIS,  Ph.D.  (Cornell) 

PROFESSOR   OF   AGRICULTURE.    SCHOOL   OF   COUNTRY  LIFE 
GEORGE   PEABODY    COLLEGE   FOR   TEACHERS,    NASHVILLE,   TENNESSEE 


COMMON  DISEASES  OF 
FARM  ANIMALS 

By  R.  a.  CRAIG,  D.V.M. 

PROFESSOR   OF   VETERINARY    SCIENCE.    PURDUE   UNIVERSITY;    AND    CHIEF    VETERINARIAN, 
PURDUE  AGRICULTURAL   EXPERIMENT   STATION 


LIPPINCOTT'S 

FARM  MANUALS 

Edited  by 

K.  C.  DAVIS.  Ph.D. 

KNAPP  SCHOOL  OF  COUNTRY  LIFE.  NASHVILLE,  TENN. 

PRODUCTIVE  SWINE  HUSBANDRY     1915 
By  GEORGE  E.  DAY,  B.S.A. 

PRODUCTIVE  POULTRY  HUSBANDRY     1919 
By  harry  R.  lewis,  B.S. 

PRODUCTIVE  HORSE  HUSBANDRY     1916 

By  carl  W.  gay,  D.V.M.,  B.S.A. 

PRODUCTIVE  ORCHARDING     1917 
By  FRED  C.  SEARS,  M.S. 

PRODUCTIVE  VEGETABLE  GROWING     1918 
By  JOHN  W.  LLOYD,  M.S.A. 

PRODUCTIVE  FEEDINGof  FARM  ANIMALS     1916 
By  F.  W.  WOLL,  Ph.D. 

COMMON  DISEASES  OF  FARM  ANIMALS     1919 
By  R.  a.  CRAIG,  D.V.M. 

PRODUCTIVE  FARM  CROPS      1918 
By  E.  G.  MONTGOMERY,  M.A. 

PRODUCTIVE  BEE  KEEPING      1918 
By  frank  C.  PELLETT 

PRODUCTIVE  DAIRYING      1919 
By  R.  M.  WASHBURN,  ALS.A. 

INJURIOUS  INSECTS  AND  USEFUL  BIRDS     1918 

By  F.  L.  WASHBURN,  M.A. 

PRODUCTIVE  SHEEP  HUSBANDRY     1918 
By  WALTER  C.  COFFEY,  M.S. 

SOIL  PHYSICS  AND  MANAGEMENT     1919 
By  J.  G.  MOSIER,  B.S.,  A.  F.  GUSTAFSON,  M.S. 


LABORATORY  MANUAL  AND  NOTEBOOK 

ON  THE  FOLLOWING  SUBJECTS 

SOILS,  By  J.  F.  EASTMAN  and  K.  C.  DAVIS     i9is 

POULTRY,  By  H.  R.  LEWIS     i9i8 

DAIRYING,  By  E.  L.  ANTHONY     i^i? 

FEEDING,  By  F.  W.  WOLL     I9i7 

FARM  CROPS,  By  F.  W.  LATHROP 


LiPPiNCOTT's  Farm  Manuals 

EDITED  BY  K.  C.  DAVIS,  Ph.D.  (Cornell) 

COMMON  DISEASES  OF 
FARM  ANIMALS 


BY 

R.  A.  CRAIG,  D.V.M. 

PROFESSOR   OF    VETERINARY   SCIENCE,    PURDUE   UNIVERSITY;    AND    CHIEF   VETERINARIAN 
PURDUE   AGRICULTUR-A.L    EXPERIMENT   STATION 


123  ILLUSTRATIONS  IN  THE  TEXT 


"  If  vain  our  toil. 
We  ought  to  blame  the  culture,  not  the  soil." 

Pops — Essay  on  Man 


THIRD  EDITION  REUSED 


PHILADELPHIA  &  LONDON 
J.  B.  LIPPINCOTT  COMPANY 


COPYRIGHT,    191  S 
BY  J.   B.  LIPPINCOTT   COMPANY 


COPYRIGHT,    I916 
BY   J.    B.   LIPPINCOTT    COMPANY 


COPYRIGHT,    I919 
BY  J.   B.  LIPPINCOTT  COMPANY 


Electrotyped  and  Printed Tiy 
J.  B.  LtPPincoU  Company,  Philadelphia,  U.  5.  A, 


PREFACE 

In  preparing  the  material  for  this  book,  the  author  has 
endeavored  to  arrange  and  discuss  the  subject  matter  in  a 
way  to  be  of  the  greatest  service  and  help  to  the  agricultural 
student  and  stockman,  and  place  at  their  disposal  a  text  and 
reference  book. 

The  general  discussions  at  the  beginning  of  the  different 
sections  and  chapters,  and  the  discussions  of  the  different  dis- 
eases are  naturally  brief.  An  effort  has  been  made  to  con- 
veniently arrange  the  topics  for  both  practical  and  class-room 
work.  The  chapters  have  been  grouped  under  the  necessary 
heads,  with  review  questions  at  the  end  of  each  chapter,  and 
the  book  divided  into  seven  parts. 

The  chapters  on  diseases  of  the  locomotory  organs,  the  teeth, 
surgical  diseases  and  castration,  although  not  commonly  dis- 
cussed in  books  of  this  class,  the  writer  believes  will  be  of  value 
for  reference  and  instructional  work. 

\Vlien  used  as  a  text-book,  it  will  be  well  for  the  instructor 
to  supplement  the  text  with  class-room  discussions. 

The  writer  has  given  special  emphasis  to  the  cause  and  pre- 
vention of  disease,  and  not  so  much  to  the  medicinal  treatment. 
Stockmen  are  not  expected  to  practise  the  medicinal  treatment, 
but  rather  the  preventive  treatment  of  disease.  For  this  reason 
it  is  not  deemed  advisable  to  give  a  large  number  of  formulas  for 
the  preparation  of  medicinal  mixtures  to  be  used  for  the  treat- 
ment of  disease,  but  such  treatment  is  suggested  in  the  most 
necessary  cases. 

R.  A.  Ceaiq. 

PuBDUE  University,  LaFayatte,  Ind. 
August,  1915. 


CU-Berkeley 

41 479a 


CONTENTS 

PART  I.— INTRODUCTORY. 


CHAPTER 


FAQB 


I.  General  Discussion  of  Disease 3 

II.  Diagnosis  and  Symptoms  of  Disease 8 

III.  Treatment 16 

PART  II.— NON-SPECIFIC  OR  GENERAL  DISEASES. 

IV.  Diseases  of  the  Digestive  System 25 

V.  Diseases  of  the  Liver 55 

VI.  Diseases  of  the  Urinary  Organs 58 

VII.  Diseases  of  the  Generative  Organs 65 

VIII.  Diseases  of  the  Respiratory  Apparatus 91 

IX.  Diseases  of  the  Circulatory  Organs 104 

X.  Diseases  of  the  Nervous  System 109 

XI.  Diseases  of  the  Skin 119 

XII.  Diseases  of  the  Eye 125 

XIII.  General  Diseases  of  the  Locomotory  Apparatus 131 

XIV.  Structure  of  the  Limbs  of  the  Horse 138 

XV.  Unsoundnesses  and  Blemishes 143 

XVI.  Diseases  of  the  Fore-Limb 147 

XVII.  Diseases  of  the  Foot 160 

XVIII.  Diseases  of  the  Hind  Limb 174 

PART  III.— THE  TEETH. 

XIX.  Determining  the  Age  of  Animals 187 

XX.  Irregularities  of  the  Teeth 196 

PART  IV.— SURGICAL  DISEASES. 

XXI.   Inflammation  and  Wounds 203 

XXII.   Fractures  and  Harness  Injuries 214 

XXIII.  Common  Surgical  Operations 219 

vii 


viii  CX)NTENTS 

PART  v.— PARASITIC  DISEASES. 
X  XIV.  Parasitic  Insects  and  Mites 233 

XXV.  Animal  Parasites 248 

PART  VI.— INFECTIOUS  DISEASES. 

XXVI.  Hog-Cholera 269 

XXVII.  Tuberculosis 283 

XXVIII.  Infectious  Diseases  Common  to  the  Different  Species  of 

Domestic  Animals 293 

XXIX.  Infectious  Diseases  of  the  Horse 309 

XXX.  Infectious  Diseases  of  Cattle  316 

XXXI.  Infectious  Diseases  of  Poultry 323 

Reference  Books 328 

Index 329 


ILLUSTRATIONS 


Fia. 


PAGE 


Insanitary  dairy  stable  and  yards Frontispiece 

1.  Side   and  posterior  view  of  bull  showing   conformation  favorable 

to  the  development  of  disease 5 

2.  Insanitary  yards 6 

3.  Showing  where  pulse  of  horse  is  taken 10 

4.  Auscultation  of  the  lungs 12 

5.  Fever  thermometer 13 

6.  Dose  syringe 18 

7.  Hypodermic  syringes 20 

8.  Photograph  of  model  of  horse's  stomach 28 

9.  Photograph  of  model  of  stomach  of  riuninant 28 

10.  Oesophageal  groove 29 

11.  Dilated  stomach  of  horse 31 

12.  Rupture  of  stomach  of  horse 32 

13.  Showing  the  point  where  the  wall  of  flank  and  rumen  are  punctured 

with  trocar  and  cannula  in  "bloat" 35 

14.  Photograph  of  model  of  digestive  tract  of  horse 39 

15.  Photograph  of  model  of  digestive  tract  of  ruminant 41 

16.  A  j'earhng  colt  that  died  of  aneurism  colic 42 

17.  Photograph  of  model  of  udder  of  cow 67 

18.  Photograph  of  model  of  uterus  of  cow  containing  foetus 79 

19.  Placenta  of  cow 83 

20.  A  case  of  milk-fever 88 

21.  Milk-fever  apparatus 89 

22.  A  case  of  catarrhal  cold 94 

23.  Photograph  of  model  of  horse's  heart 104 

24.  Elephantiasis  in  horse 107 

25.  Photograph  of  model  of  horse's  brain 110 

26.  Unilateral  facial  paralysis 112 

27.  Bilateral  facial  paralysis 112 

28.  Skeleton  of  horse 131 

29.  Photograph  of  model  of  stifle  joint 132 

30.  Atrophy  of  the  muscles  of  the  thigh 135 

31.  Shoulder  lameness 147 

32.  Shoe-boil 149 

33.  Sprung  knees 152 

34.  Sphnts 152 

ix 


X 


ILLUSTRATIONS 


35.  Bones  of  digit 158 

36.  Photograph  of  a  model  of  the  foot 160 

37.  Foot  showing  neglect  in  trimming  wall 161 

38.  A  very  large  side  bone 162 

39.  A  case  of  navicular  disease 164 

40.  An  improperly  shod  foot 165 

41.  Toe-cracks 168 

42.  Quarter-crack  caused  by  barb-wire  cut 168 

43.  Changes  occurring  in  chronic  laminitis 172 

44.  Atrophy  of  the  muscles  of  the  quarter 175 

45.  String-halt 1^*^ 

46.  A  large  bone  spavin 178 

47.  Capped  hock 179 

48.  Bog  spavins 1°0 

49.  Thorough  pin 181 

50.  Curbs 183 

51.  Head  of  young  horse  showing  position  and  size  of  teeth 187 

52.  Longitudinal  section  of  incisor  tooth 189 

53.  Cross-section  of  head  of  young  horse,  showing  replacement  of  molar 

tooth 190 

54.  Transverse  section  of  incisor  tooth 191 

55.  Transverse  sections  of  incisor  tooth  showing  changes  at  different 

ages 192 

56.  Teeth  showing  uneven  wear  occurring  in  old  horses 198 

57.  Fistula  of  jaw 199 

58.  A  large  hock  caused  by  a  punctured  wound  of  the  joint 207 

59.  A  large  inflammatory  growth  following  injury 208 

60.  Fistula  of  the  withers 212 

60a.  Fistula  of  the  region  of  the  poll  of  the  head 213 

61.  Shoulder  abscess  caused  by  loose-fitting  harness 216 

62.  A  piece  of  the  wall  of  the  horse's  stomach  showing  bot-fly  larvae 

attached 234 

63.  Biting  louse 237 

64.  Sucking  louse 238 

65.  Nits  attached  to  hair 238 

66.  Sheep-tick 241 

67.  Sheep  scab  mite 242 

68.  Sheep  scab 243 

69.  A  severe  case  of  mange 245 

70.  Liver  flukes 248 

71.  Tapeworm  larvie  in  liver 250 

72.  Tapeworms 250 

73.  Tapeworm  larva?  in  the  peritoneum 251 

74.  Thorn-headed  worms 2oo 


ILLUSTRATIONS  xi 

75.  Large  round-worm  in  intestine  of  hog 254 

76.  Lamb  affected  with  stomach  worm  disease 258 

77.  Whip-worms  attached  to  wall  of  intestine 260 

78.  Pin-worms  in  intestine 260 

79.  A  hog  yard  where  disease-producing  germs  may  be  carried  over 

from  year  to  year 270 

80.  Carcass  of  a  cholera  hog 274 

8L  Kidnej^s  from  hog  that  died  of  acute  hog-cholera 275 

82.  Lungs  from  hog  that  died  of  acute  hog-cholera 275 

83.  A  piece  of  intestine  showing  intestinal  ulcers 276 

84.  Cleaning  up  a  hog  lot 278 

85.  HjTJerimmune   hogs   used  for  the  production  of  anti-hog-cholera 

serum 280 

86.  Preparing  the  hog  for  vaccination 281 

87.  Vaccinating  a  hog 281 

88.  Koch's  Bacillus  tuberculosis 283 

89.  Cows  affected  with  tuberculosis 286 

90.  Tubercular  spleens 287 

91.  The  carcass  of  a  tubercular  cow 288 

92.  A  section  of  the  chest  wall  of  a  tubercular  cow 289 

93.  A  very  large  tubercular  gland 290 

94.  A  tubercular  gland  that  is  spht  open 291 

95.  Caul  showing  tuberculosis 291 

96.  Foot  of  hog  showing  tuberculosis  of  joint 291 

97.  Staphylococcus  pyogenes 293 

98.  Streptococcus  pyogenes 293 

99.  Bacillus  of  malignant  oedema,  showing  spores 294 

100.  Bacillus  of  malignant  oedema 294 

101.  Bacillus  septicemia  hemorrhagica 295 

102.  A  yearling  steer  affected  with  septicemia  hemorrhagica 296 

103.  Bacillus  anthracis 297 

104.  Bacillus  necrophorus 299 

105.  Negri  bodies  in  nerve-tissue 300 

106.  A  cow  affected  with  foot-and-mouth  disease 303 

107.  Federal  inspector  examining  mouth  of  suspected  case  of  foot-and- 

mouth  disease '^O^ 

108.  Washing  coat  and  boots  with  disinfectant  after  inspecting  herd 305 

109.  Inspector  fumigating  clothing 305 

110.  Bacillus  tetani 306 

HI.  Head  of  horse  affected  with  tetanus 307 

1 12.  A  subacute  case  of  tetanus 308 

113.  Streptococcus  of  strangles 309 

114.  Bacillus  mallei 312 

115.  Longitudinal  section  of  head  of  horse  having  glanders 313 


xii  ILLUSTRATIONS 

116.  Streptococcus  pyogenes  equi 314 

117.  A  case  of  "lumpy  jaw" 316 

118.  The  ray  fungus 317 

119.  Bacillus  of  emphysematous  anthrax 319 

120.  Cattle  tick  (male) 320 

121.  Cattle  tick  (female) 320 

122.  Blood-cells  with  Piroplasma  bigeminum  in  them !21 

123.  Bacillus  avisepticus 323 


PART  I 

INTRODUCTORY 


COMMON  DISEASES  OF 
FARM  ANIMALS 


CHAPTER  I 
GENERAL  DISCUSSION  OF  DISEASE 

Disease  is  the  general  term  for  any  deviation  from  the 
normal  or  liealtliy  condition  of  the  hody.  The  morbid  processes 
that  resnlt  in  either  slight  or  marked  modifications  of  the  normal 
condition  are  recognized  by  the  injurious  changes  in  the  struct- 
ure or  function  of  the  organ,  or  group  of  body  organs  involved. 
The  increase  in  the  secretion  of  urine  noticeable  in  horses  in  the 
late  fall  and  winter  is  caused  by  the  cool  weather  and  the  decrease 
in  the  perspiration.  If,  however,  the  increase  in  the  quantity 
of  urine  secreted  occurs  independently  of  any  normal  cause  and 
is  accompanied  by  an  unthrifty  and  weakened  condition  of  the 
animal,  it  would  then  characterize  disease.  Tissues  may  undergo 
changes  in  order  to  adapt  themselves  to  different  environments, 
or  as  a  means  of  protecting  themselves  against  injuries.  The 
coat  of  a  horse  becomes  heavy  and  appears  rough  if  the  animal 
is  exposed  to  severe  cold.  A  rough,  staring  coat  is  very  common 
in  horses  affected  by  disease.  The  outer  layer  of  the  skin  be- 
comes thickened  when  subject  to  pressure  or  friction  from  the 
harness.  This  change  in  structure  is  purely  protective  and 
normal.  In  disease  the  deviation  from  normal  must  be  more 
permanent  in  character  than  it  is  in  the  examples  mentioned 
above,  and  in  some  way  prove  injurious  to  the  body  functions. 

Classification. — We  may  divide  diseases  into  three  classes: 
non-specific,  specific  and  parasitic. 

Non-specific  diseases  have  no  constant  cause.     A  variety  of 

3 


4  :''.:  t'l  ,•'■  "  ,  '  TNTECPUCTORY 

causes  may  produce  the  same  disease.  For  example,  acute  indi- 
gestion may  be  caused  by  a  change  of  diet,  watering  the  animal 
after  feeding  grain,  by  exhaustion  and  intestinal  worms. 
Usually,  but  one  of  the  animals  in  the  stable  or  herd  is  affected. 
If  several  are  affected,  it  is  because  all  have  been  subject  to 
the  same  condition,  and  not  because  the  disease  has  spread  from 
one  animal  to  another. 

Specific  Diseases. — The  terms  infectious  and  contagious  are 
used  in  speaking  of  specific  diseases.  Much  confusion  exists  in 
the  popular  use  of  these  terms.  A  contagious  disease  is  one  that 
may  be  transmitted  by  personal  contact,  as,  for  example,  in- 
fluenza, glanders  and  hog-cholera.  As  these  diseases  may  be 
produced  by  indirect  contact  with  the  diseased  animal  as  well  as 
by  direct,  they  are  also  infectious.  There  are  a  few  germ  dis- 
eases that  are  not  spread  by  the  healthy  animals  coming  in  direct 
contact  with  the  diseased  animal,  as,  for  example,  black  leg 
and  southern  cattle  fever.  These  are  purely  infectious  diseases. 
Infection  is  a  more  comprehensive  term  than  contagion,  as  it 
may  be  used  in  alluding  to  all  germ  diseases,  while  the  use  of 
the  term  contagion  is  rightly  limited  to  such  diseases  as  are 
produced  principally  through  individual  contact. 

Parasitic  diseases  are  very  common  among  domestic  animals. 
This  class  of  disease  is  caused  by  insects  and  worms,  as  for  ex- 
ample, lice,  mites,  ticks,  flies,  and  round  and  flat  worms  that 
live  at  the  expense  of  their  hosts.  They  may  invade  any  of 
the  organs  of  the  body,  but  most  commonly  inhabit  the  digestive 
tract  and  skin.  Some  of  the  parasitic  insects,  mosquitoes,  flies 
and  ticks,  act  as  secondary  hosts  for  certain  animal  micro- 
organisms that  they  transmit  to  healthy  individuals  through  the 
punctures  or  the  bites  that  they  are  capable  of  producing  in  the 
skin. 

Causes. — For  convenience  we  may  divide  the  causes  of 
disease  into  the  predisposing  or  indirect,  and  the  exciting  or 
direct. 


GENERAL  DISCUSSION  OF  DISEASE  5 

The  predisposing  causes  are  such  factors  as  tend  to  render 
the  body  more  susceptible  to  disease  or  favor  the  presence  of  the 
exciting  cause.  For  example,  an  animal  that  is  narrow  chested 
and  lacking  in  the  development  of  the  vital  organs  lodged  in 
the  thoracic  cavitv,  when  exposed  to  the  same  condition  as  the 
other  members  of  the  herd,  may  contract  disease  while  the 
animals  having  better  conformation  do  not  (Fig.  1).  Hogs 
confined  in  well-drained  yards  and  pastures  that  are  free  from 
filth,  and  fed  in  pens  and  on  feeding  floors  that  arc  clean,  do 


Fig.   1. — (A)  side  and  (B)  posterior  view  of  bull  showing  conformation  favorable  to  the 
development  of  disease. 

not  become  hosts  for  large  numbers  of  parasites.  Hogs  confined 
in  filthy  pens  are  frequently  so  badly  infested  with  lice  and  intes- 
tinal worms  that  their  health  and  thriftiness  are  seriously  inter- 
fered with.  In  the  first  case  mentioned  the  predisposition  to 
disease  is  in  the  individual,  and  in  the  second  case  it  is  in  the 
surroundings  (Fig.  2). 

The  exciting  causes  are  the  immediate  causes  of  the  par- 
ticular disease.  Exciting  causes  usually  operate  through  the 
environment.  With  the  exception  of  the  special  disease-produc- 
ing germs,  the  most  common  exciting  causes  are  faulty  food  and 


6  INTRODUCTORY 

faulty  methods  of  feeding.     The  following  predisposing  causes 
of  disease  may  be  mentioned: 

Age  is  an  important  factor  in  the  production  of  disease. 
Young  and  immature  animals  are  more  prone  to  attacks  of  infec- 
tious diseases  than  are  old  and  mature  animals.  Ilog-cholera 
usually  affects  the  young  hogs  in  the  herd  first,  while  scours, 
suppurative  joint  disease  and  infectious  sore  mouth  are  dis- 
eases that  occur  durincr  the  first  few  days  or  few  weeks  of  the 


' — ' '  jri. 


Fig.  2. — Insanitary  yards. 

animal's  life.  Lung  and  intestinal  parasites  are  more  commonly 
found  in  the  young,  growing  animals.  Old  animals  are  prone  to 
fractures  of  bones  and  degenerative  changes  of  the  body  tissues. 
As  a  general  rule,  the  young  are  more  subject  to  acute  diseases 
and  the  old  to  chronic  diseases. 

The  surroundings  or  environments  are  important  predis- 
posing factors.  A  dark,  crow^dcd,  poorly  ventilated  stable  lowers 
the  animal's  vitality,  and  renders  it  more  susceptible  to  the 
disease.     A  few  rods  difference  in  the  location  of  stables  and 


GENERAL  DISCUSSION  OF  DISEASE  7 

yards  may  make  a  marked  diifereiice  in  the  health  of  the  herd. 
A  dry,  protected  site  is  always  preferable  to  one  in  the  open 
or  on  low,  poorly  drained  soil.  The  majority  of  domestic  animals 
need  but  little  shelter,  but  they  do  need  dry,  comfortable  quarters 
during  wet,  cold  weather. 

Faulty  feed  and  faulty  methods  of  feeding  are  very  common 
causes  of  diseases  of  the  digestive  tract  and  the  nervous  system. 
A  change  from  dry  feed  to  a  green,  succulent  ration  is  a  common 
cause  of  acute  indigestion  in  both  horses  and  cattle.  The  feeding 
of  a  heavy  ration  of  grain  to  horses  that  are  accustomed  to  exer- 
cise, during  enforced  rest  may  cause  liver  and  kidney  disorders. 
The  feeding  of  spoiled,  decomposed  feeds  may  cause  serious 
nervous  and  intestinal  disorders. 

One  attach  of  a  certain  disease  may  influence  the  develop- 
ment of  subsequent  attacks  of  the  same,  or  a  different  disease. 
An  individual  may  suffer  from  an  attack  of  pneumonia  that  so 
w^eakens  the  disease-resisting  powers  of  the  lungs  as  to  result  in 
a  tubercular  infection  of  these  organs.  In  the  horse,  one  attack 
of  azoturia  predisposes  it  to  a  second  attack.  One  attack  of 
an  infectious  disease  usually  confers  immunity  against  that 
particular  disease. 

Heredity  does  not  play  as  important  a  part  in  the  develop- 
ment of  diseases  in  domestic  animals  as  in  tlie  human  race.  A 
certain  family  may  inherit  a  predisposition  to  disease  through 
the  faulty  or  insufficient  development  of  an  organ  or  group  of 
organs.  The  different  species  of  animals  are  affected  by  dis- 
eases peculiar  to  that  particular  species.  The  horse  is  the  only 
species  that  is  affected  with  azoturia.  Glanders  affects  solipeds, 
while  black  leg  is  a  disease  peculiar  to  cattle. 

QUESTIONS 

1.  What  is  disease? 

2.  How  are  diseases  classified?     Give  an  example  of  the  different  classes. 

3.  What  is  a  predisposing  cause?     Exciting  cause? 

4.  Name  the  different  predisposing  and  exciting  causes  of  disease. 


CHAPTER  II 
DIAGNOSIS  AND  SYMPTOMS  OF  DISEASE 

The  importance  of  recognizing  or  diagnosing  the  seat  and 
nature  of  the  morbid  change  occurring  in  an  organ  or  group  of 
organs  cannot  be  overestimated.  Laymen  do  not  comprehend 
the  difficulty  or  importance  of  correctly  grouping  the  signs  or 
symptoms  of  disease  in  such  a  way  as  to  enable  them  to  recognize 
the  nature  of  the  disease.  In  order  to  be  able  to  understand  the 
meaning  of  the  many  symptoms  or  sigiis  of  disease,  we  must  pos- 
sess knowledge  of  the  structure  and  physiological  functions  of 
the  different  organs  of  the  body.  We  must  be  familiar  with  the 
animal  when  it  is  in  good  health  in  order  to  be  able  to  recognize 
any  deviation  from  the  normal  due  to  disease,  and  we  must  learn 
from  personal  observation  the  different  symptoms  that  charac- 
terize the  different  diseases.  Stockmen  should  be  able  to  tell 
when  any  of  the  animals  in  their  care  are  sick  as  soon  as  the 
first  symptom  of  disease  manifests  itself,  by  changes  in  the 
general  appearance  and  behavior.  But  in  order  to  ascertain 
the  exact  condition  a  general  and  systematic  examination  is 
necessary.  The  examiner,  whether  he  be  a  layman  or  a  veteri- 
narian, must  observe  the  animal  carefully,  noting  the  behavior, 
appearance,  surroundings,  and  general  and  local  symptoms. 

Before  making  a  general  exam'mation  of  the  animal  it  is  well, 
if  the  examiner  is  not  already  acquainted  with  the  history  of  the 
case  (care,  feed  and  surroundings),  to  learn  as  much  about  this 
from  the  attendant  as  is  possible.  Inquiry  should  be  made  as 
to  the  feeding,  the  conditions  under  which  the  animal  has  been 
kept,  the  length  of  time  it  has  been  sick,  its  actions,  or  any  other 
information  that  may  be  of  assistance  in  forming  the  diagnosis 
and  outlining  the  treatment. 

The  general  symptoms  inform  us  regarding  the  condition  of 
8 


DIAGNOSIS  AND  SYMPTOMS  OF  DISEASE  9 

the  different  groups  of  body  organs.  A  careful  study  of  this 
group  of  symptoms  enables  us  correctly  to  diagnose  disease  and 
inform  ourselves  as  to  the  progress  of  long,  severe  affections. 
These  symptoms  occur  in  connection  with  the  pulse,  respirations, 
body  temperature,  skin  and  coat,  visible  mucous  membranes, 
secretions  and  excretions,  and  behavior  of  the  aninuil. 

The  local  symptoms  are  confined  to  a  definite  part  or  organ. 
Swelling,  pain,  tenderness  and  loss  of  function  are  common  local 
s;)Tnptoms.  A  direct  symptom  may  also  be  considered  under  this 
head  because  of  its  direct  relation  to  the  seat  of  disease.  It  aids 
greatly  in  forming  the  diagTiosis. 

Other  terms  used  in  describing  s^miptoms  of  disease  are 
ohjectiue,  which  includes  all  that  can  be  recognized  by  the  person 
making  the  examination ;  indirect,  which  are  observed  at  a  dis- 
tance from  the  seat  of  the  disease;  and  premonitory,  which 
precede  the  direct,  or  characteristic  sjanptoms.  The  subjective 
s_Nanptoms  include  such  as  are  felt  and  described  by  the  patient. 
These  symptoms  are  available  from  the  human  patient  only. 

Pulse. — The  character  of  the  intermittent  expansion  of  the 
arteries,  called  the  pulse,  informs  us  as  to  the  condition  of  the 
heart  and  blood-vessels.  The  frequency  of  the  pulse  beat  varies 
in  the  different  species  of  animals.  The  smaller  the  animal  the 
more  frequent  the  pulse.  In  young  animals  the  number  of  beats 
per  minute  is  greater  than  in  adults.  Excitement  or  fear,  espe- 
cially if  the  animal  possesses  a  nervous  temperament,  increases 
the  frequency  of  the  pulse.  During,  and  for  a  short  time  after, 
feeding  and  exercise,  the  pulse  rate  is  higher  than  when  the 
animal  is  standing  at  rest. 

The  following  table  gives  the  normal  rate  of  the  pulse  beats 
per  minute : 

jlorse    36  to     40  por  minute 

Ox   45  to     50  per  minute 

gheep    70  to     80  per  minute 

Piff    70  to     SO  per  minute 

Dog  90  to  100  per  minute 


10 


INTRODUCTORY 


In  sickness  the  pulse  is  instantly  responsive.  It  is  of  the 
greatest  aid  in  diagnosing  and  in  noting  the  progi"ess  of  the 
disease.  The  following  varieties  of  pulse  may  be  mentioned: 
frequent,  infrequent,  quick,  slow,  large,  small,  hard,  soft  and 
intermittent.  The  terms  frequent  and  infrequent  refer  to  the 
number  of  pulse  beats  in  a  given  time;  quick  and  slow  to  the 
length  of  time  required  for  the  pulse  wave  to  pass  beneath  the 
finger;  large  and  small  to  the  volume  of  the  wave;  hard  and 
soft  to  its  compressibility;  and  intermittent  to  the  occasional 

missing  of  a  beat.  A  pulse 
beat  that  is  small  and  quick, 
or  large  and  soft,  is  fre- 
quently met  with  in  dis- 
eases of  a  serious  character. 
The  horse's  pulse  is  taken 
from  the  submaxillary  ar- 
tery at  a  point  anterior  to, 
or  below  the  angle  of  the  jaw 
and  along  its  inferior  border 
(Fig.  3).  It  is  here  that 
the  artery  winds  around  the 
inferior  border  of  the  jaw  in 
an  upward  direction,  and,  be- 
cause of  its  location  immediately  beneath  the  skin,  it  can  be  read- 
ily located  by  pressing  lightly  over  the  region  with  the  fingers. 
Cattle's  pulse  is  taken  from  the  same  artery  as  in  the  horse. 
The  artery  is  most  superficial  a  little  above  the  border  of  the  jaw. 
It  is  more  difficult  to  find  the  pulse  wave  in  cattle  than  it  is  in 
horses,  because  of  the  larger  amount  of  connective  tissue  just 
beneath  the  skin  and  the  heavier  muscles  of  the  jaw.  A  very 
satisfactory  pulse  may  be  found  in  the  small  arteries  located 
along  the  inferior  part  of  the  lateral  region  of  the  tail  and  near 
its  base. 

The  sheep's  pulse  may  be  taken  directly  from  the  femoral 


Fig.  3. — The  X  on  the  lower  border  of  the 
jaw  indicates  the  place  where  the  pulse  is  taken. 


DIAGNOSIS  AND  SYMPTOMS  OF  DISEASE  11 

aitery  bj  placing  the  fingers  over  tlic  inner  region  of  the  thigh. 
Ej  pressing  with  the  hand  over  the  region  of  the  lieart  we  may 
determine  its  condition. 

The  hoij's  pulse  can  easily  be  taken  from  the  femoral  artery 
on  the  internal  region  of  the  thigh.  The  artery  crosses  this 
region  obliquely  and  is  quite  superficial  toward  its  anterior  and 
lower  portion. 

The  dog's  pulse  is  usually  taken  from  the  brachial  artery. 
The  pulse  wave  can  be  readily  felt  by  resting  the  fingers  over 
the  inner  region  of  the  arm  and  just  above  the  elbow.  The  charac- 
ter of  the  heart  beats  in  dogs  may  be  determined  by  resting  the 
hand  on  the  chest  wall. 

Respiration. — The  frequency  of  the  respirations  varies  with 
the  species.  The  following  table  gives  the  frequency  of  the 
respirations  in  domestic  animals : 

Horse    8  to  10  per  minute 

Ox 12  to  15  per  minute 

Sheep 12  to  20  per  minute 

Dog   15  to  20  per  minute 

Pig 10  to  15  per  minute 

The  ratio  of  the  lieart  beats  to  the  respirations  is  about 
1 :  4  or  1 :  5.  This  ratio  is  not  constant  in  ruminants.  Rumina- 
tion, muscular  exertion  and  excitement  increase  the  frequency 
and  cause  the  respirations  to  become  irregular.  In  disease  the 
ratio  between  the  heart  beats  and  respirations  is  greatly  dis- 
turbed, and  the  character  of  the  respiratory  sounds  and  move- 
ments may  be  greatly  changed  (Fig.  4). 

Severe  exercise  and  diseased  conditions  of  the  lungs  cause 
the  animal  to  breathe  rapidly  and  bring  into  use  all  of  the  respira- 
tory muscles.  Such  forced  or  labored  breathing  is  a  common 
symptom  in  serious  lung  diseases,  ''  bloat  "  in  cattle,  or  any  con- 
dition that  may  cause  dyspnoea.  Horses  affected  with  "  heaves  " 
show  a  double  contraction  of  the  muscles  in  tlie  region  of  the 
flank    during    expiration.     In    spasm    of    the    diaphragm    or 


12 


INTRODUCTORY 


"  thumps  "  the  expiration  appears  to  he  a  short,  jerking  move- 
ment of  the  tlank.  In  the  abdominal  form  of  respiration  the 
movements  of  the  walls  of  the  chest  are  limited.  This  occurs  in 
pleurisy.  In  the  thoracic  form  of  respiration  the  abdominal 
wall  is  held  rigid  and  the  movement  of  the  chest  walls  make  up 
for  the  deficiency.     This  latter  condition  occurs  in  peritonitis. 


Fic 


-Auscultation  of  the  lungs  can  be  practised   to  an  advantage   over   the  outlined 
portion  of  the  chest  wall,  only. 


A  cough  is  caused  by  irritation  of  the  membrane  lining  the 
air  passages.  The  character  of  the  cough  may  vary  according  to 
the  nature  of  the  disease.  We  may  speak  of  a  moist  cough  when 
the  secretions  in  the  air  passages  are  more  or  less  abundant. 
A  dry  cough  occurs  when  the  lining  membrane  of  the  air  passages 
is  drv  and  inflamed.     This  mav  occur  in  the  earlv  statre  of  the 


DIAGNOSIS  AND  SYMPTOMS  OF  DISEASE  13 

inflammation,  or  as  a  result  of  irritation  frt)m  dust  or  irritatinii^ 
gases.  Chronic  eongh  occurs  when  the  disease  is  of  long  dura- 
tion or  chronic.  In  pleurisy  the  cough  may  be  short  and  painful, 
and  in  broken  wind,  deep  and  suppressed.  In  parasitic  diseases 
of  the  air  passages  and  lungs,  the  paroxysm  of  coughing  may  be 
severe  and  "  husky  "  in  character. 

The  odor  of  the  expired  air,  the  character  of  the  discharge 
and  the  respiratory  sounds  found  on  making  a  careful  examina- 
tion are  important  aids  in  arriving  at  a  correct  diagnosis,  and 
in  studying  the  progress  of  the  disease. 

Body  Temperature. — The  body  temperature  of  an  animal  is 
taken  by  inserting  the  fever  thermometer  into  the  rectum.  In 
large  animals  a  tive-inch,  and  in  small  aninuils  a  four-inch 
fever  thermometer  is  used.      It  should  be  inserted  full  length 

^mm^^^^t^"^'^-  '  |iiii|i|ii|liiT|iiii[ii|i|iiii[iiil[iiii|iiii|iiii[llii[ilil|illi|ilii[iiini|li| 

>-    VS/ 

Fig.   5. — Fever  thermometer. 

and  left  in  position  from  one  and  one-half  to  three  minutes, 
depending  on  the  rapidity  witli  which  it  registers    (Fig.   5), 
The  average  normal  body  temperatures  of  domestic  animals 
are  as  follows: 

Horses  100.5"  F. 

Cattle 101.4°  F. 

Sheep 104.0°  F. 

Swine 103.0°  F. 

Dog 101.4°  F. 

There  is  a  wide  variation  in  the  body  temperatures  of  domes- 
tic animals.  This  is  especially  true  of  cattle,  sheep  and  hogs. 
In  order  to  determine  the  normal  temperature  of  an  animal,  it 
may  be  necessary  to  take  two  or  more  readings  at  different  times, 
and  compare  them  with  the  body  temperatures  of  other  animals 
in  the  herd  that  are  known  to  be  healthy. 

Exercise,    feeding,    rumination,    excitement,    warm,    close 


14  INTRODUCTORY 

stables,  exposure  to  cold  and  drinking  ice  cold  water  are  common 
causes  of  variations  in  the  body  temperatures  of  domestic 
animals. 

Visible  Mucous  Membranes. — The  visible  mucous  mem- 
branes, as  they  are  tenned,  are  the  lining  membranes  of  the  eye- 
lids, nostrils  and  nasal  cavities,  and  mouth.  In  health  they  are 
usually  a  pale  red,  excepting  when  the  animal  is  exercised  or 
excited,  when  they  appear  a  brighter  red  and  somewhat  vascular. 
In  disease  the  following  changes  in  color  and  appearance  may 
be  noted :  When  inilamed,  as  in  cold  in  the  head,  a  deep  red ; 
in  impoverished  or  bloodless  conditions  of  the  body  and  in 
internal  hemorrhage,  pale;  in  diseases  of  the  liver,  sometimes 
yellowish,  or  dark  red ;  in  diseases  of  the  digestive  tract  (buccal 
mucous  membrane),  coated;  if  inflamed,  dry  at  first,  later  ex- 
cessively moist ;  and  in  certain  gei-m  diseases  a  mottled  red,  or 
showing  nodules,  ulcers  and  scars. 

Surface  of  the  Body. — ^^llen  a  horse  is  in  a  good  condition 
and  well  cared  for,  the  coat  is  short,  fine,  glossy  and  smooth  and 
the  skin  pliable  and  elastic.  Healthy  cattle  have  a  smooth, 
fflossv  coat  and  the  skin  feels  mellow  and  elastic.  The  fleece 
of  sheep  should  appear  smooth  and  have  plenty  of  yolk,  the  skin 
pliable  and  light  pink  in  color.  When  the  coat  loses  its  lustre 
and  gloss  and  the  skin  becomes  hard,  rigid,  thickened  and  dirty, 
it  indicates  a  lack  of  nutrition  and  an  unhealthy  condition  of 
the  body.  In  sheep,  during  sickness,  the  wool  may  become  dry 
and  brittle  and  the  skin  pale  and  rigid.  When  affected  with 
external  parasites,  the  hair  or  wool  becomes  dirty  and  rough, 
a  part  of  the  skin  may  be  denuded  of  hair,  and  it  appears  thick- 
ened, leathery  and  scabby,  or  shows  pimples,  vesicles  and  sores. 

During  fever,  the  temperature  of  the  surface  of  the  body  is 
very  unequal.  In  serious  diseases  or  diseases  that  are  about  to 
terminate  fatally,  the  skin  feels  cold  and  the  hair  is  wet  with 
sweat. 

When  animals  are  allowed  to  "  rough  it "  during  the  cold 


DIAGNOSIS  AND  SYMPTOMS  OF  DISEASE    ■  15 

weather,  the  coat  of  hair  becomes  heavy  and  rough.  This  is  a 
provision  of  nature  and  enables  them,  as  long  as  the  coat  is  dry, 
to  withstand  severe  cold. 

Horses  that  are  in  a  low  physical  condition,  or  when  accus- 
tomed to  hard  work,  if  then  kept  in  a  stall  for  a  few  days  without 
exercise,  commonly  show  a  filling  of  the  cannon  regions  of  the 
posterior  extremities.  This  condition  also  commonly  occurs  in 
disease  and  in  mares  that  have  reached  the  latter  period  of 
pregnancy.  Sheep  that  are  unthrifty  and  in  a  poor  physical  con- 
dition, especially  if  this  is  due  to  internal  parasites,  frequently 
develop  dropsical  swellings  in  the  region  of  the  jaw,  or  neck. 

Body  Excretions. — The  character  of  the  body  excretions, 
fiieces  and  urine  may  become  greatly  changed  in  certain  diseases. 
It  is  important  that  the  stockman  or  veterinarian  obsem^e  these 
changes,  and  in  certain  diseases  make  an  analysis  of  the  urine. 
This  may  be  necessary  in  order  properly  to  diagnose  the  case. 

Behavior  of  the  Animal. — When  tlie  body  temperature  is 
high,  the  animal  may  appear  greatly  depressed.  If  suffering 
severe  pain,  it  may  be  restless.  In  diseases  of  the  nervous  sys- 
tem, the  behavior  of  the  animal  may  be  greatly  changed. 
Spasms,  convulsions,  general  local  paralysis,  stupid  condition  and 
unconsciousness  may  occur  as  symptoms  of  this  class  of  disease. 

QUESTIONS 

1.  What  information  is  necessary  in  order  to  be  able  to  recognize  or  diag- 

nose disease? 

2.  What  are  the  general  symptoms  of  disease? 

3.  W^hat  are  the  subjective  symptoms  of  disease? 

4.  Describe  method  of  taking  the  pulse  beat  in  tlie  different  animals  and  its 

character  in  health  and  disease. 

5.  Give  the  ratio  of  the  heart  beats  to  the  respirations  in  the  different  species 

of  animals. 

6.  What  are  the  normal  body  temperatures  in  the  different  domestic  animals  ? 

7.  What  are  the  visible  mucous  membranes? 

8.  Is  the  condition  of  the  coat  and   skin  any  help   in  the   recognition  of 

disease  ? 


CHAPTER  III 

TREATMENT 

Preventive  Treatment. — The  subject  of  preventive  medicine 
becomes  more  important  as  our  knowledge  of  the  cause  of  disease 
advances.  A  knowledge  of  feeds,  methods  of  feeding,  care, 
sanitation  and  the  use  of  such  biological  products  as  bacterins, 
vaccines  and  protective  serums  is  of  the  greatest  importance 
to  the  farmer  and  veterinarian.  We  are  begimiing  to  realize  that 
one  of  the  most  important  secrets  of  profitable  and  successful 
stock  raising  is  the  prevention  of  disease ;  that  the  agricultural 
colleges  are  doing  a  great  w^ork  in  helping  to  teach  farmers 
that  there  are  right  and  wrong  methods  of  feeding  and  caring 
for  animals ;  that  the  practice  of  sanitation  in  caring  for  animals 
is  the  cheapest  method  of  treating  disease ;  and  that  it  is  advisable 
to  practise  radical  methods  of  control,  when  necessary,  in  order 
to  rid  the  herd  of  an  infectious  disease. 

The  raiion  fed  and  the  method  of  feeding  are  not  only  im- 
portant in  considering  the  causes  of  diseases  of  the  digestive 
tract,  but  diseases  of  other  organs  as  well.  The  feeding  of  an 
excessive,  or  insufficient  quantity  of  feed,  or  a  ration  that  is  too 
concentrated,  bulky  and  innutritions,  poor  in  quality,  or  spoiled 
may  produce  disease. 

An  impure  water  supply  is  a  common  cause  of  disease.  A 
deep  well  that  is  closed  in  properly  and  does  not  permit  of  con- 
tamination from  filth,  does  not  insure  a  clean  water  supply  if 
the  trough  or  tank  is  not  kept  clean. 

Farm  Buildings.- — If  stockmen  would  make  a  more  careful 

study  of  the  kind  of  farm  buildings  most  suitable  to  their  needs, 

the  selection  of  the  location,  the  proportions,  the  arrangement 

of  the  interior  and  the  lighting  and  ventilation,  there  would  be 

16 


TREATMENT  17 

a  great  saving  in  losses  from  disease,  and  the  cost  of  building  in 
many  cases  would  be  lessened.  Your  neighbor's  building  that 
YOU  have  taken  for  your  model  may  not  be  suitable  for  your 
needs.  It  may  be  more  expensive  than  your  financial  condition 
permits.  It  may  be  poorly  lighted  and  ventilated  and  not  suited 
to  the  site  that  you  have  selected. 

Biological  Products. — There  are  a  number  of  biological  prod- 
ucts that  may  be  used  in  the  prevention  and  control  of  disease. 
Some  of  these  products,  such  as  tuberculin  and  malein,  enable  the 
owner  to  rid  his  herds  of  tubercular  cows  and  glandered  horses 
before  these  diseases  have  become  far  enough  advanced  to  be 
recognized  by  the  visible  s^Tuptoms  alone.  Black  leg,  anthrax 
and  hog-cholera  vaccines  are  valuable  agents  in  the  control  of 
disease.  In  the  treatment  of  fistula  and  infectious  abortion, 
bacterins  may  be  used.  There  are  many  other  germ  diseases  and 
infections  for  which  vaccines  and  bacterins  may  be  used.  How- 
ever, we  must  not  depend  wholly  on  these  agents  in  the  control  of 
disease.  We  must  possess  a  knowledge  of  the  manner  in  which 
the  infection  is  spread,  for  without  this  knowledge  we  would  be 
unable  to  prevent  its  dissemination  over  a  wide  area. 

Medicinal  Treatment. —  The  average  stockman  or  veteri- 
narian is  more  familiar  with  the  treatment  of  disease  with  drugs 
than  he  is  with  the  preventive  measures  just  described.  This 
statement  does  not  imply  that  a  knowledge  of  medicinal  thera- 
peutics is  not  of  the  greatest  importance  in  the  treatment  of 
disease.  The  ultimate  object  of  all  drugs  is  both  to  prevent  and 
cure  disease,  but  the  injudicious  use  of  a  drug  does  neither.  A 
discussion  of  this  subject  cannot  be  entered  into  here,  and  because 
of  its  largeness  it  is  not  advisable  to  discuss  it  further  than  a 
brief  summary  of  the  methods  of  administering  drugs. 

Administration  of  Drugs. — Drugs  may  be  administered  by 
the  following  chamiels :  by  way  of  the  mouth,  in  the  feed  or  as  a 
drench ;  by  injecting  into  the  tissues  beneath  the  skin  or  hypo- 
2 


18 


INTRODUCTORY 


dermically ;  by  rubbing  into  the  skin  ;  by  the  air  passages  and  the 
lungs;  and  by  injecting  into  the  rectum. 

•i"t>  If  the  animal  is  not  too  sick  to  eat  and  the  drug  does  not 
possess  an  unpleasant  taste,  it  may  be  given  with  the  feed.  If 
soluble,  it  may  be  given  with  the  drinking  water,  or  in  any  case, 
it  may  be  mixed  with  ground  feed  if  this  method  is  to  be  pre- 
ferred. In  all  eases  the  medicine  must  be  well  mixed  with  the 
feed.  This  is  especially  important  if  there  are  a  number  of 
animals  to  be  treated,  as  there  is  more  certainty  of  each  animal 
getting  the  proper  dose  and  the  danger  of  overdosing  is  avoided. 
If  the  young  animal  is  nursing  the  mother,  we  can  take  advantage 
of  certain  drugs  being  eliminated  in  the  mothec's j v^ii^-, ^»d 
administer  the  drug  to  the  mother.  '  i'-    >..[  l-ar 

jfroijiode  p.rfoil-uVtifi 


Fig.  6.— a  good  kind  of  a  dose  syringe.  'tJOSIfll  6u 

Drenches. — In  the  larger  animals  a  bulky  drench; is. ;§pme- 
times  difficult  to  administer,  and  we  should,  in  all  cases,  count 
on  a  portion  being  wasted. 

Horses  are  sometimes  difficult  to  drench,  and  it  may  be 
advisable  to  confine  the  horse  in  some  wa^.  Small  drenches  can 
re,a,dily  be  given  with  a  syringe  (Fig.  6)  or  a  small  bottle.  In 
giving  bulky  drenches  it  is  most  convenient  to  use  a  long-necked, 
heavy  glass  bottle.  The  horse  should  be  backed  into  a  narrow 
stall  and  the  head  elevated  by  placing  a  loop  in  the  end  of  a  small 
rope  over  the  upper  jaw,  passing  the  rope  back  of  the  nose  piece 
on  the  halter  and  throwing  it  over  a  beam,  and  raising  the  head 
until  the  mouth  is  slightly  higher  than  the  throat.  If  tlie  horse 
refii^esto  swallow,  a  tablespoonful  of  clean  water  may  be  dropped 
into  the  nostril.     This  forces  it  to  swallow.     A  dreilch  should 


TREATMENT  19 

never  be  given  through  the  nose,  as  it  may  pass  into-tUe-jaiT 
passages  and  cause  a  fatal  inflammation  of  the  hiiigs.     ■•-,  ;,-,•  i 

Cattle  can  be  easily  drenched  bv  taking  hold  of  the  nostrils 
with  the  fingers,  or  snapping  a  bull  ring  into  the  partition 
between  the  nostrils  and  elevating  the  head. 

Sheep  may  be  drenched  either  in  the  standing  position,  or 
when  throwTi  on  the  haunches  and  held  between  the  knees.  Care 
should  be  exercised  in  giving  irritating  drenches  to  sheep,  esp(h 
cially  if  the  drench  be  bulky. 

A  herd  of  hogs  may  be  quickly  and  easily  drenched  if  they 
are  confined  in  a  small  pen,  and  the  loop  of  a  small  rope  placed 
around  the  snout,  well  back  toward  the  corners  of  the  mouth.  A 
small  metal  dose  syringe  should  be  used.  If  the  drench  is  bulky 
and  the  hog  difficult  to  hold,  it  may  be  necessary  to  elevate  the 
head  and  raise  the  forefeet  from  the  ground.  The  drench 
should  not  be  given  until  the  hog  is  quiet  and  well  under  control, 
as  there  is  some  danger  of  the  medicine  passing  into  the  air 
passages  and  doing  harm.  It  may  be  necessary  to  mark  the 
hogs  that  have  been  drenched  with  a  daub  of  paint,  or  in  some 
other  manner  in  order  to  be  able  to  distinguish  them  from  the 
untreated  animals. 

The  administration  of  drugs  enclosed  in  a  gelatin  capsule,  or 
mixing  them  with  syrup,  honey  or  linseed  oil,  and  rolling  the 
mass  into  the  form  of  a  cylinder  is  commonly  practised.  The 
capsule  or  hall  may  then  be  shot  into  the  pharynx  with  a  balling 
gun.  A  ball  may  also  be  given  to  the  larger  animals  by  carrying 
it  into  the  back  part  of  the  mouth  with  the  hand,  and  placing  it 
on  the  back  part  of  the  tongue.  In  the  horse  this  method  of 
administration  requires  some  practice.  The  tongue  must  ba 
pulled  well  forward,  the  head  held  up,  and  the  tongue  released 
as  soon  as  the  ball  is  placed  on  the  tongue,  so  that  it  may  pass 
back  into  the  pharynx.  ■,,^  ci 

The  administration  of  drugs  by  injecting  heneath  the  shin 
(Fig.  7)  is  suitable  when  the  drug  is  non-irritating  and  the 


20 


INTRODUCTORY 


dose  is  small.  Drugs  administered  iii  this  way  act  promptly  and 
energetically.  The  alkaloid  or  active  principle  of  the  drug  is 
commonly  used.  A  fold  of  the  skin  is  picked  up  with  the  fingers 
and  tlie  needle  is  quickly  introduced,  care  being  taken  not  to 
prick  or  scratch  the  muscular  tissue,  as  this  causes  some  pain  and 
makes  the  animal  restless.  In  order  to  avoid  abscess  formation 
at  the  point  of  injection,  the  skin  should  be  cleansed  with  a  disin- 
fectant and  the  syringe  and  needle  sterilized  before  using. 

Drugs  are  not  absorbed  through  the  unbroken  skin,  but  when 
applied  with  friction,  or  when  the  outer  layer  is  removed  by 


Fio.  7. — Hypodermic  syringes. 

blistering,  absorption  may  take  place.  Liniments,  blisters  and 
poultices  are  the  preparations  used. 

Volatile  drugs,  such  as  chloroform  and  ether,  are  absorbed 
quickly  by  the  enormous  vascular  surface  of  the  lungs.  This 
class  of  drugs  is  administered  for  the  purpose  of  producing 
general  anaesthesia.  Ancpsthetics  are  indispensable  in  many 
surgical  operations. 

The  administration  of  a  drug  in  the  form  of  medicated  steam 
is  quite  useful  in  combating  some  respiratory  diseases.  In 
steaming  large  animals  a  pail  about  half  full  of  boiling-hot  water 
to  which  has  been  added  about  an  ounce  of  coal-tar  disinfectant, 


TREATiMENT  21 

or  whatever  drug  is  required,  is  held  within  about  one  f(xit 
of  the  aninial's  nostrils.  It  is  usually  advisable  to  throw  a  light 
cover  over  the  head  and  pail  in  order  to  direct  the  steam  toward 
the  nostrils.  Dogs  can  be  placed  on  a  cane-seated  chair  and  a 
pail  or  pan  of  boiling-hot  water  placed  under  it,  and  a  sheet 
thrown  over  all. 

Drugs  are  administered  by  way  of  the  rectum  when  the 
animal  can  not  be  drenched,  or  the  drug  can  not  be  given  in 
any  other  way  and  when  a  local  action  is  desired.  An  enema 
or  clyster  is  a  fluid  injection  into  the  rectum  and  is  employed 
for  the  following  purposes:  to  accelerate  the  action  of  a  purga- 
tive ;  to  stimulate  the  peristaltic  movement  of  the  intestines ;  to 
kill  intestinal  parasites ;  to  reduce  body  temperature  ;  to  adminis- 
ter medicine;  and  to  supply  the  animal  with  food.  An  enema 
may  be  administered  by  allowing  water  to  gravitate  into  the  rec- 
tum from  a  height  of  two  or  three  feet  or  by  using  an  injection 
pump.  In  the  larger  animals  several  feet  of  heavy  walled  rubber 
tubing  carrying  a  straight  nozzle  at  one  end  should  be  used.  In 
administering  an  enema,  the  rectum  should  be  emptied  out  with 
the  hand  and  the  nozzle  of  the  syringe  carried  as  far  forward  as 
possible.  The  operator  should  be  careful  not  to  irritate  or  tear 
the  wall  of  the  rectum. 

Size  of  the  Dose. — The  doses  recommended  in  the  treatment 
of  the  different  diseases,  unless  otherwise  stated,  are  for  mature 
animals.  The  dose  for  a  colt  one  year  of  age  is  about  one-third 
the  quantity  given  the  adult,  two  years  of  age  one-half,  and  three 
years  of  age  two-thirds.  In  well-matured  colts  a  larger  dose  may 
be  given.  In  cattle,  the  doses  recommended  are  about  the  same. 
In  the  smaller  animals  the  size  of  the  dose  may  be  based  on  the 
development  and  age  of  the  animal.  When  the  drug  is  adminis- 
tered at  short  intervals  or  repeated,  the  size  of  the  dose  should  be 
reduced.  The  physiological  action  of  some  drugs  may  be  changed 
by  varying  the  size  of  the  dose. 


32 


INTRODUCTORY 


1    ,,;    .,(;  QUESTIONS 

I'jIGiVe  a  general  description  of  preventive  treatment. 

2.  By  what  channels  may  drugs  be  administered? 

3.  How  are  drenches  administered? 

4.  How  are  solid  drugs  administered?  '^"^  8<iOVi 

5.  What  kind  of  drugs  are  administered  liypodermically?  ''!.,   nfiq  TO  IlBq 

6.  What  is  an  enema?  ,.  •,.);■, l  u.-O'fift 

7.  What  proportion  of  the  dose  of  a  drug  recommended  for  the  adult  may  be 
t-iiiJ  giygn  i0  immature  animals? 


■  /^^aiiff  10 
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IBV  ^d 


PART  II 
NON-SPECIFIC  OR  GENERAL  DISEASES 


CHAPTER  IV 
DISEASES  OF  THE  DIGESTIVE  SYSTEM 

The  organs  that  form  the  digestive  tract  are  the  mouth, 
phar;)aix,  oesophagus,  stomach,  intestines  and  the  annexed  glands, 
viz. :  the  salivary,  liver,  and  pancreas.  The  development  of  these 
organs  differs  in  the  different  species  of  animals.  For  example, 
solipeds  possess  a  small,  simple  stomach  and  capacious,  compli- 
cated intestines.  Just  the  opposite  is  true  of  ruminants.  The 
different  species  of  ruminants  possess  a  large,  complicated 
stomach,  and  comparatively  simple  intestines.  In  sv^^ine  we  meet 
with  a  more  highly  developed  stomach  than  that  of  solipeds 
and  a  more  simple  intestinal  tract.  Of  all  domestic  animals  the 
most  simple  digestive  tract  occurs  in  the  dog.  These  variations 
in  the  development  of  the  different  organs  of  digestion,  together 
with  the  difference  in  the  character  of  the  feed  and  method  of 
feeding,  cause  a  variation  in  the  kind  of  diseases  met  with  in 
the  different  species.  The  complicated  stomach  of  ruminants 
predispose  them  to  diseases  of  this  portion  of  the  digestive  tract. 
Because  of  their  complicated  intestinal  tract  solipeds  are  prone 
to  intestinal  disease. 

DISEASES   OF    THE   MOUTH 

General  Discussion. — The  mouth  is  the  first  division  of  the 
digestive  tract.  It  is  formed  by  the  lips,  cheeks,  palate,  soft 
palate,  tongue  and  teeth.  Here  the  feed  is  acted  on  mechanically. 
It  is  broken  up  by  the  teeth  and  moved  about  until  mixed  with 
the  saliva  and  put  into  condition  to  pass  through  the  pharynx  and 
along  the  oesophagTis  to  the  stomach.  The  mechanical  change 
that  the  feed  is  subject  to  is  very  imperfect  in  dogs.  In  the 
horse  it  is  a  slow,  thorough  process,  although  greedy  feeders  are 
not  uncommon.  The  first  mastication  in  the  ox  is  three  times 
quicker  than  in  horses,  but  the  process  of  rumination  is  slow  and 
thorough. 

25 


26  NON-SPECIFIC  OR  GENERAL  DISEASES 

Stomatitis. — Simple  inflammation  of  the  mouth  is  frequently 
met  with  in  horses.    Ulcerative  or  infectious  inflammation  com- 
monly occut«s  iii"^>tffiiBg/  ianid'^GCc^sioiiaOyiti -old,  debilitated  ani- 
n^als.    This  form  of  sore  mouth  Avill  be  discussed  along  with  other 
infectious  diseases,  and  the  following  disc^f^ssioft  i^JI,]),^  cjanfif^^ 
to  the  npn^iufectipus  form  of  the  disease.     ,  ,n    /  ,i:-!\hi>.  fn't  :  .sh 
^l^^^e,  qay^es  a?e,;rjcitatipn  6:pp^.;thie  bit,  sharp  teeth, •irj^ita.tmg, 
drenches,  roughage  that  contains  beards  or  awns  of  grasses  and 
grains,  and  burrs  that  wound  the  lining  membrane  of  the  mou.tl^,., 
Febrile,  or  digestive  disorders,  or  any  condition  that  may  in.t^rr', 
fere  with  feeding,  may  cai^se  tl^is,  disprder.     In  the  latter  cases 
the  mucous  membrane  of  the  mouth  is  not  cleansed  by  the  saliva. 
Particles  of  feed  may  decompose  and  irritating  organisms  set^u^^ 
an  inflammation.     I^utrid^p^i  dec^opiposed,  slops,,, 1^9;t.f^e(^fi,  ^jir^ 
tjg^Tig  .Frenches  aiid  (irinking  ,f rom  filthy  >\:allp,\Y8r-^.rp,.5i9mmon: 
causes  of  inflammation' of  the  mouth  inhpgs.  ,,   ,     •;;;,  ...:,  ,-'.  ,., 

The  sy)nplo])is  vary  in  ^he  different  cases  and  species.  ..Slight 
gy,4ocali?^cl: ^nflammatipji , ,of  ithe,, mouth  is  usually  ,pye^l,ookp4 
by,  the  attendant.  Lampas  of  horses  may  be  considered  a  local 
inflammation  involving  the  palate.  Lacerations  of  .the  chepk 
or  tongue  by  the  teeth,  or  irritating  feed,  usually  result  in,  a, slight 
interference  with  prehension  and  mastication  and  more  or  less 
salivation.  Salivation  from  this  cause  should  not  be  ccnfused 
With  salivation  resulting  from  feeding  on  white  clover. 
ii(;niii  generalized  inflatoiVi'Ation  of '  the 'mticobs  mtem'bi'k'iie, 'Siie 
fii^^t'^ymj)t'Ptti  Tisually  noti<?ed  ife' the  iiiability  t-o' eat:  On  exani4 
iiiing  the  mouth  we  find  the  mucous  mfembrane  inflame'd,  hot  and 
dry.  A  part  may  appear  coated.  In  a  short  time  the  odor  from 
tJie  mmith  is  f«tid.  Following  thi&  dry  stage  of  the  inflammation 
is  the  period  of  salivation.  Saliva  dribbles  from  the  mouth,  and 
in  severe  cases  it  is  mixed  with  white,  stringy  shreds  of  epithe- 
lium and  tinged  with  blood.  In  less  acute  fbi-ms  Pf 'the  difeieas'ej 
we  may  notice  little  blisters -G'r'¥fe^i«ele^' Scattered  over  the  liiiirig 
membrane  of  the  lips,  cheeks  and  tongue.  ...^ij.yioai 


DISEASES  OF  THE  DIGESTIVE  SYSTEM  27 

The  acute  form  of  stomatitis  runs  a  short  course,  usually 
a  few  davs,  and  responds  readily  to  treatment.  Localized  in- 
flammation, caused  by  irritation  from  teeth,  ot  feeding  irritating 
feeds,  does  not  respond  so  readily  to  treatment., '!'■  l''iiiuM5<!;;  -^jM 

The  treat nient  is  largely  preventive  and  consists' largely i-i' 
removing  the  cause.  When  the  mouth  is '  inflained,  roughage 
should  he  fed  rather  sparingly,  and  soft  feeds  suen '8(3  slopS^' 
mashes,  or  gruels  given  in  place  of  the  regular  diet.  Plenty  of 
clean  drinking  water  should  be  provided.  In  the  way  of  medic- 
inal treatment  antiseptic  and  astringent  washes  are  indicated.  A 
four  per  cent  water  solution  of  boric  acid  may  be  used,  or  a  one- 
half  per  cent  water  solution  of  a  high  grade  coal-tar  disinfectant. 
The  mouth  should  be  thoroughly  irrigated  twice  daily  until  the 
mucous  surfaces  appear  normal. 

DEPRAVED   APPETITE 

^^;A  depraved  appetite  is  met  with  in  all  species  of  farm  ani- 
mals, but  it  is  especially  common  in  ruminants.  It  should  not 
be  classed  as  a  disease,  but  more  correctly  as  a  bad  habit,  or 
s^^nptonl  of  innutrition  or  indigestion.  The  animals  affected 
seem  to  have  an  irresistible  desire  to  lick,  chew  and  swallow  indi- 
gestible and  disQUstinff  obiectSi;n:>.v-, « -jMuii  i,.  !>;.. 

The  common  cause  of  depraved  appetite  is  the  feeding  oi  a 
ration  deficient  in  certain  food  elements.  A  ration  deficient  in 
protein  or  in  salts  is  said  to  cause  this  disorder.  Lack  of  exerrj 
cise,  or  confinement,  innutrition,  and  a  depraved  sense  of  taste 
may  favor  tliQ  development  of  this  disease.  Eor  example,  when 
sheep  are  housed  closely  they  may  contract  the  habit  of  chewing 
one  another's  fleeces.  Lambs  are  especially,  apti  ta.eocutract  this 
habit  when  suckling  ewes  that  have  on  their  udders  long  wool 
soiled  with  urine  and  frcces. 

ffi{{rhe  )fimtr,S'j^mptom  is  the  desire  to  chew,  lick  or  eat  indi- 
gestible or  filthy  substances.  Horses  and  cattle  may  stand  and 
IieJ§-^,j3^ard  for  an  hour  or  more;  cattle  may  chew  the  long  hair 


28 


NON-SPECIFIC  OR  GENERAL  DISEASES 


from  the  tails  of  horses ;  sheep  may  nibble  wool ;  sows  may  within 
a  short  time  after  giving  birth  to  their  pigs,  kill  and  eat  them ; 
chickens  may  pick  and  eat  feathers.  Innutrition  may  accompany 
the  abnormal  appetite,  as  very  frequently  the  affected  animal 
shows  a  disposition  to  leave  its  feed  in  order  to  eat  these  injurious 
and  innutritions  substances.  In  ruminants,  the  wool  or  hair 
may  form  balls  and  obstruct  the  opening  into  the  third  compart- 
ment, causing  chronic  indigestion  and  death. 

The  treatment  consists  in  the  removal  of  the  cause.    Feeding 
a  ration  that  meets  the  needs  of  the  system,  clean  quarters  and 


Fig.  8. 


Fig.  9. 


Fig.  8. — Photograph  of  model  of  horse's  stomach:     (A)  left  portion,  (C)  oesophagus,  (D) 

right  portion,  and  (E)  intestine. 

Fig.  9. — Photograph  of  model  of  stomach  of  ruminant:     (A)  rumen,  (B)  reticulum,  (C) 

omasum,  and  (£)  abomasum, 

plenty  of  exercise  are  the  most  important  preventive  lines  of 
treatment.  In  such  cases  medicinal  treatment  (saline  and  bitter 
tonics)  may  be  indicated.  It  is  usually  advisable  to  remove  the 
affected  animals  from  the  herd  or  flock  in  order  to  prevent  others 
from  imitating  them. 


DISEASES    OF    THE    STOMACH 


There  is  a  remarkable  difference  in  the  development  of  the 
stomachs  of  solipeds  and  ruminants. 

The  horse's  stomach  (Fig.  8)  is  simple  and  has  a  capacity 


DISEASES  OF  THE  DIGESTIVE  SYSTEM 


29 


of  three  or  four  gallons.  The  left  portion  is  lined  with  a  cnticuhtr 
mucous  membrane,  and  the  right  portion  with  a  glandular 
mucous  membrane  that  has  in  it  the  glands  that  secrete  the 
gastric  juice.  The  most  important  digestive  change  in  the  feed 
is  the  action  of  the  gastric  juice  on  the  proteids  and  their  conver- 
sion into  the  simpler  products,  proteoses  and  peptones. 

Ruminants  have  a  compound  stomach  (Figs.  9  and  10). 
The  capacity  of  the  stomach  of  the  ox  is  between  twenty  and 
thirty  gallons.     The  four  compartments  into  which  it  is  divided 


Fig.   10. — AvSection  of  the  wall  of  the  rumen  and  reticulum,  showing  the  oesophageal  groove: 
(C,  C)   lips  of  groove;  (B)  opening  from  cesophagus;  and  (A)  opening  into  omasum. 

are  the  rumen,  reticulum,  omasum,  and  abomasum  or  true  stom- 
ach. The  rumen  is  the  largest  compartment,  with  a  capacity  of 
more  than  twenty  gallons.  The  reticulum  is  the  smallest,  with 
a  capacity  of  about  one-half  gallon. 

After  a  brief  mastication,  the  food  passes  directly  to  the 
rumen.  Here  it  is  subjected  to  a  churning  movement  that  mixes 
and  presses  the  contents  of  the  rumen  forward  in  the  direction 
of  the  oesophageal  opening,  where  it  is  ready  for  regurgitation. 
It  is  then  carried  back  to  the  mouth,  remasticated  and  returned 


so  NON-SPECIFIC  OR  GENERAL  DISEASES 

to  the  nimen.  This  is  teiined  mmiiiation.  All  fond  material 
that  is  sufficiently  broken  np  is  directed  toward  the  opening 
into  the  third  compartment  by  thfe  oesophageal  grove  ('Fig.  lOy, 
a'  demi-canal  that  connects 'tliis' with  the  oesophageal  opening!.' sg 
'  The  third  compartment,  the  owa,sw7«/ communicates  anteri- 
orly with  the  second  and  first,  and  posteriorly  with  the  fourth 
conipartmeiit  &!•  trtie  ktomacli.  Th^  ihterfor  arraftgeitient  bf  this 
compartment  is  mdst'  sihgul'^r.  ^" '  1%'  'is '  '■divided  by  a '  rmiiibeif'  of 
Targe  folds  of  the  li'nfng'membmn'e 'between  ■svhieli'''aVe'sm'a^^ 
folds.     It  is  between  these  folds  that  the  contents  pass. 

The  first  three  compartments  possess  no  glands  capable  of 
secreting  a  digestive  juice.  However,  important  digestive 
changes  occur.  The  carbohydrates  are  digested  by  means  of 
enzymes  contained  in  the  feed.  The  most  important  function  of 
the  rumen  and  omasum  is  the  maceration  of  the  fibrous  sub- 
stances, and  the  digestion  of  the  cellulose.  Between  sixty  and 
seventy  per  cent  of  the  cellulose  is  digested  in  the  rumen. 

The  ahomasum  is  lined  by  a  gastric  nmcous  membrane.  The 
gastric  juice  secreted  converts  the  protein  into  peptones.  In  the 
young  a  milk  curdling  ferment  is  also  secreted  by  the  glands  of 
this  compartment. 

The  stomach  of  the  hog  is  a  ty^e  between  the  carnivora  and 
ruminant.  The  digestive  changes  may  be  divided  into  four 
stages.  The  first  period  is  one  of  starch  conversion ;  the  second 
period  is  the  same,  only  more  pronounced ;  the  third  period,  both 
^tarch  and  protein  conversion  occurs;  and  the  fourth  period  is 
taken  up  mostly  with  protein,  digestion. 

iiTn--  ^  -        •       ■  ■■         .    :■■  .<vri<    (r;:flt   -^infn 

Acute  Indigestion  of  the  Stomach  of  Solipeds. — Diseases  of 
the  stomach  are  less  common  in  solipeds  than  in  ruminants.  The 
simple  stomach  of  the  horse  and  the  comparatively  unimportant 
place  that  it  occupies  iu  the  digestion  of  the  feed  renders  it  less 
subject  to  disease.  Only  under  the  most  unfavorable  conditions 
for  digestion  of  the  feed  does  this  class  of  disorders  occur.    Acute 


DISEASES  OF  THE  DIGESTIVE  SYSTEM 


31 


iiKligestion  in  the  form  of  overloadin^c:  and-  feiTnentation  oocurS 
in  the  stomach  (Fig.  11)1  '"^  ■"^'-  ,  trvyo,.).  ,.v/ur  oilt  ^o 

ni  ntpjiie  ^^^^%)0si7i^'mw^!efr^1;hat'h'avfe  todo'With  thei  development 
of  these  disorders,  are  the  small  capacity  of  the  stomach  and 
the  location  and  smallness  of  the  openings  leading  from  the 
crsophagns  and  into  the  siiiall  intestines.  Greedy  eaters  are 
more  prone  to  indigestion  than  animals  that  eat  slowly  arid  are 
fed  intelligently. 

The  following  exciting  causes  may  be  mentioned:  Sudden 


Fio.    11. — Dilated  stomach  of  horse. 


changes  in  ration ;  feeding  too  much  green  feed  or  grain ;  feed- 
ing frozen  or  decomposed  feeds;  drinking  ice-cold  water;  and 
violent  exercise  or  work  that  the  animal  is  not  accustomed  to, 
immediately  after  feeding  are  the  common  disease-producing 
factors.  ■^)  ^^^''^ 

.s.v,ir/ie  symptQms/maj  YQ.r J  irom  impaired  appetite  and 'slight 
restlessness  to  violent,  colicky  pains.  In  the  large  majority  of 
cases  the  attendant  is  unable  to  differentiate  between  tliis  and 
other  forms  of  acute  indigestion.  The  characteristic  symptoms 
are  attempts  at  regiii-gitation  and  vomiting,  assuming  a  dog-sit- 


32 


NON-SPECIFIC  OR  GENERAL  DISEASES 


ting  position  and  finally  such  nervous  s^anptoms  as  champing 
of  the  jaws,  staggering  movement  and  extreme  dulness. 

The  violent  form  of  gastric  indigestion  frequently  ends  in 


Fig.   12. — Rupture  of  stomach  of  Kbrse.' 

death.     Rupture  of  the  stomach  is  not  an  uncommon  complica- 
tion (Fig.  12). 

The  treatment  is  both  preventive  and  medicinal.  This  diges- 
tive disorder  can  be  prevented.  The  feeding  of  the  right  kind 
of  a  ration  and  in  the  right  way,  and  avoiding  conditions  that 
may  interfere  with  tlie  digestion  of  the  feed,  are  the  general 
lines  of  preventive  treatment  indicated.     Such  measures  are  of 


DISEASES  OI<   THE  DIGESTIVE  SYSTEM  33 

special  importance  in  the  handling  of  animals  that  possess  an 
individual  predisposition  toward  this  class  of  disease.  In  mild 
attacks  the  animal  should  ho  suhjccted  to  a  rigid  or  careful  diet 
during  the  attack  and  for  a  few  days  later. 

It  is  advisable  to  place  the  animal  in  a  comfortable  stall  that 
is  well  bedded  with  straw  and  plenty  large  for  it  to  move  about 
in.  If  a  roomy  sick-stall  can  not  be  provided,  a  grass  lot  or  l)arn 
floor  nuiy  be  used.  If  the  weather  is  chilly  or  cold,  the  ])ody 
should  be  covered  with  a  blanket  and  roller  bandages  applied 
to  the  limbs. 

Bulky  drenches  should  not  be  given.  Stimulants  and  drugs 
capable  of  retarding  fermentation  are  indicated.  Sometimes 
the  administration  of  a  sedative  is  indicated.  Treatment  should 
be  prompt,  as  in  many  cases  fermentation  of  the  contents  of  the 
stomach  occurs  and  gases  form  rapidly.  From  two  to  four  ounces 
of  oil  of  turpentine  may  be  given  in  from  six  to  eight  ounces 
of  linseed  oil. 

'  Acute  Indigestion  of  the  Stomach  of  Ruminants. — The  dif- 
ferent forms  of  acute  indigestion  are  bloating,  overloading  of 
the  rumen  and  impaction  of  the  omasum. 

Tympanites,  "  Bloating." — This  disorder  is  usually  caused 
by  animals  feeding  on  green  feeds,  such  as  clover,  alfalfa  and 
green  corn,  that  ferment  readily.  Stormy,  rainy  weather  seems 
to  favor  bloating.  The  consumption  of  spoiled  feeds  such  as 
potatoes  and  beets  may  cause  it.  The  drinking  of  a  large  quan- 
tity of  water,  especially  if  cold,  chills  the  wall  of  the  rumen  and 
interferes  with  its  movement.  Frozen  feeds  may  act  in  the  same 
way.  Sudden  changes  in  the  feed,  inflammation  of  the  rumen, 
and  a  weak  peristaltic  movement  of  the  paunch  resulting  from 
disease  or  insufficient  nourishment  are  frequent  causes.  It  may 
occur  in  chronic  disease.  In  tuberculosis,  bloating  sometimes 
occurs. 

The  symptoms  are  as  follows:  The  paunch  or  rumen  occu- 
pies the  left  side  of  the  abdominal  cavity,  hence  the  distention  of 
3 


34  NON-SPECIFIC  OR  GENERAL  DISEASES 

the  abdominal  wall  by  the  collecting  of  gas  in  the  rumen  occurs 
principally  on  that  side.  The  gas  forms  quickly  and  the  dis- 
tended wall  is  highly  elastic  and  resonant.  The  animal  stops 
eating  and  ruminating,  the  back  may  be  arched  and  the  ears 
droop.  In  the  more  severe  cases  the  wall  of  the  abdomen  is 
distended  on  both  sides,  the  respirations  are  quickened  and 
labored,  the  pulse  small  and  quick,  the  eyes  are  prominent  and 
the  mucous  membrane  congested.  Death  results  from  asphyxia 
brought  on  by  the  distended  paunch  pushing  forward  and  inter- 
fering with  the  movement  of  the  lungs  and  the  absorption  of  the 
poisonous  gases. 

Tlic  ircdiment  is  both  preventive  and  medicinal.  This  form 
of  acute  indigestion  can  be  largely  prevented  by  practising  the 
following  preventive  measures:  All  changes  in  the  feed  should 
be  made  gradually,  especially  if  the  ration  fed  is  heavy,  or  the 
new  ration  consists  largely  of  green,  succulent  feed.  Cattle 
pasturing  on  clover  should  be  kept  under  close  observation.  It 
is  not  advisable  to  pasture  cattle  on  rank  growths  of  clover  that 
are  wet  with  dew  or  a  light  rain.  Bloating  can  be  quickly  re- 
lieved by  puncturing  the  wall  of  the  paunch  with  the  trocar 
and  cannula.  The  operation  is  quite  simple  and  is  not  followed 
by  bad  results.  The  instrument  is  plunged  through  the  walls  of 
the  abdomen  and  rumen  in  the  most  prominent  portion  of  the 
flank,  midway  between  the  border  of  the  last  rib  and  the  point 
of  the  haunch  (Fig.  13).  The  trocar  is  then  withdrawn  from 
the  cannula.  After  the  gas  has  escaped  through  the  cannula, 
the  trocar  is  replaced  and  the  instrument  withdrawn.  After 
using  the  trocar  and  cannula,  the  instrument  should  be  cleaned 
by  placing  it  in  boiling  hot  water.  It  is  advisable  to  wash  the 
skin  at  the  seat  of  the  operation  with  a  disinfectant  before  oper- 
ating. In  chronic  t^Tupanitis,  it  is  sometimes  advisable  to  leave 
the  cannula  in  position  by  tying  a  tape  to  the  flange,  passing  it 
around  the  body  and  tying. 

As  a  cathartic  for  cattle,  we  may  give  one  quart  of  linseed  oil 


DISEASES  OF  THE  DIGESTIVE  SYSTEM 


35 


and  from  two  to  four  ounces  of  turpentine,  or  one  to  two  pounds 
of  Epsom  or  Glauber's  salts,  dissolved  in  plenty  of  water.  Sheep 
may  be  g-iven  about  one-fourth  the  dose  reconnncnded  for  cattle. 
Overloading  the  Rumen. — This  form  of  indigestion  occurs 
when  ruminants  have  access  to  feeds  that  they  are  not  accus- 
tomed to.  As  a  result,  they  eat  greedily  and  the  mass  of  feed  in 
tlie  rumen  becomes  so  heavv  that  the  walls  of  the  oraan  can  not 


Fig.   13. — The  X  indicates  the  point  where  the  wall  of  flank  and  rumen  are  punctured  with 
trocar  and  cannula  in  "bloat." 

move  it  about,  and  digestion  is  interfered  with.  This  is  espe- 
cially true  of  succulent  feeds.  A  diseased  condition  of  the  ani- 
mal predisposes  it  to  this  disorder.  If  after  eating  an  excessive 
amount  of  dry,  innutritions  fodder,  the  animal  drinks  freely  of 
cold  water,  acute  s^inptoms  of  overloading  are  manifested. 

The  general  symptoms  occurring  in  overloading  resembles 
those  seen  in  bloating.  The  symptoms  may  be  mild  and  extend 
over  a  period  of  several  days,  or  it  may  take  on  a  highly  acute 


36  NON-SPECIFIC  OR  GENERAL  DISEASES 

form,  terminating  fatally  within  a  few  hours.  The  aciiteness  of 
the  attack  depends  on  the  character  and  quantity  of  feed  eaten. 
If  a  large  quantity  of  green  feed  is  eaten,  fermentation  occurs 
and  the  animal  may  die  within  a  few  hours.  The  swelling  on 
the  left  side  has  a  doughy  feel.  It  is  not  as  elastic  and  resonant 
as  in  bloat,  even  when  complicated  by  some  gas  formation.  The 
animal  may  stop  ruminating,  refuse  to  eat,  and  act  dull.  In  the 
more  severe  cases  the  respirations  are  hurried  and  labored,  the 
pulse  small  and  quick  and  the  expression  of  the  face  indicates 
pain.  Colicky  pains  sometimes  occur.  Death  may  occur  from 
shock  or  asphyxia. 

The  treatment  is  both  preventive  and  curative.  This  disease 
can  be  prevented  by  using  the  necessary  precautions  to  prevent 
animals  from  overeating.  If  gas  forms,  the  trocar  and  cannula 
should  be  used.  A  drench  of  from  one  to  two  pounds  of  Epsom 
or  Glauber's  salts  should  be  given.  Sheep  may  be  given  from 
four  to  six  ounces  of  Epsom  or  Glauber's  salts.  We  should 
endeavor  to  stimulate  the  movement  of  the  paunch  by  pressure 
on  the  flank  with  the  hand,  throwing  cold  water  on  the  wall  of 
the  abdomen  and  by  hypodermic  injections  of  strychnine.  Ru- 
menotomy  should  be  performed  when  necessary.  This  operation 
consists  in  opening  the  walls  of  the  abdomen  and  rumen,  and 
removing  a  part  of  the  contents  of  the  rumen.  This  is  not  a 
dangerous  operation  when  properly  performed,  and  should  not 
be  postponed  until  the  animal  is  too  weak  to  make  a  recovery. 

Impaction  of  the  Omasum. — This  disease  may  occur  as  a 
complication  of  other  forms  of  acute  indigestion  and  diseases 
accompanied  by  an  abnormal  body  temperature.  Feeds  that  are 
dry  and  innutritions  commonly  cause  it.  Other  causes  are  an 
excessive  quantity  of  feed,  sudden  changes  in  the  diet  and  drink- 
ing an  insufficient  quantity  of  water. 

As  in  other  diseases  of  the  stomach,  the  appetite  is  dimin- 
ished, rumination  ceases  or  occurs  at  irregular  intervals,  and  the 
animal  is  more  or  less  feverish.    Bloating  and  constipation  may 


DISEASES  OF  THE  DIGESTIVE  SYSTEM  37 

occur.  The  animal  may  lose  flesh,  is  weak,  walks  stiffly  and 
grunts  as  though  in  pain  when  it  moves  about  in  the  stall  and 
at  each  respiration.  In  the  acute  form,  marked  symptoms  are 
sometimes  manifested.  At  first  the  animal  acts  drowsy ;  later 
violent  nervous  symptoms  may  develop. 

The  course  of  this  disease  varies  from  a  few  days  to  several 
weeks.  Death  frequently  occurs.  Frequently  a  diarrlK^a  accom- 
panies recovery,  a  portion  of  the  fa?ces  appearing  black  with 
polished  surfaces,  as  though  they  had  been  baked. 

The  preventive  treatment  consists  in  practising  the  necessary 
precautions  against  the  development  of  this  disease  by  avoiding 
sudden  changes  in  the  feed,  the  feeding  of  dry,  innutritions  feeds 
in  too  large  amounts,  allowing  animals  plenty  of  water  and  pro- 
viding them  with  salt.  The  best  purgative  to  give  is  Glauber's 
or  Epsom  salts  in  from  one-  to  two-jjound  doses,  dissolved  in  at 
least  one  gallon  of  water.  This  physic  may  be  repeated  in  from 
twelve  to  eighteen  hours  if  necessary.  Two  drachms  of  tincture 
of  nux  vomica  and  one  ounce  of  alcohol  may  be  given  in  a  drench 
three  times  daily.  Hypodermic  injections  of  strychnine,  eserine, 
or  pilocarpine  are  useful  in  the  treatment  of  this  disease.  When 
recovery  begins,  the  animal  should  be  allowed  moderate  exercise 
and  be  fed  food  of  a  laxative  nature. 

Foreign  Bodies  in  the  Stomach  of  Ruminants. — Foreign 
bodies  such  as  hair  balls  and  wire  are  very  commonly  found  in 
the  reticulum.  This  is  because  of  the  habits  of  this  class  of  ani- 
mals. Cattle  eat  their  feed  hastily  and  do  not  pick  it  over  as 
carefully  as  does  the  horse. 

Smooth,  round  objects  do  no  appreciable  harm  unless  they 
block  the  opening  into  the  third  compartment  of  the  stomach. 
This  frequently  occurs  in  w^ool-eatiug  lambs.  vSharp-pointed  ob- 
jects may  penetrate  the  surrounding  tissues  or  such  organs  as  the 
spleen,  diaphragm,  and  pericardial  sack.  If  these  organs  are 
injured  by  the  foreign  body  serious  s^^nptoms  develop.  The 
general  symptoms  are  pain,  fever,  weakness  and  marked  emacia- 


38  NON-SPECIFIC  OR  GENERAL  DISEASES 

tion.  It  is  very  difficult  to  form  a  correct  ditigiiosis,  as  the  disease 
comes  on  without  any  apparent  cause.  Sometimes  a  swelling  is 
noticed  in  the  right  and  inferior  abdominal  region.  If  the  heart 
becomes  injured,  symptoms  of  pericarditis  are  manifested. 

The  treatment  is  largely  preventive.  Special  care  should 
be  used  to  avoid  getting  foreign  substances  into  the  feed  given 
to  cattle.  The  feed  troughs  should  be  kept  clean ;  we  should  avoid 
dropping  nails  and  staples  into  the  feed  when  repairing  the  silo 
or  grain  bin ;  and  pieces  of  baling  wire  should  be  removed  from 
straw  or  hay.  Feeds  known  to  be  dirty  should  be  run  through 
a  fanning  mill  before  feeding. 

Inflammation  of  the  Stomach  of  Swine. — Overloading  and 
feeding  spoiled  feed  are  common  causes  of  inflammation  of  the 
stomach.  Swill-fed  hogs  are  most  commonly  affected  with  this 
disorder.  Overloading  more  often  results  in  an  inflammation  of 
the  stomach  if  the  overloading  follows  the  feeding  of  a  light 
ration,  and  the  weather  is  extremely  warm.  Hogs  that  are  accus- 
tomed to  eating  salt  may  eat  too  much  of  it  when  fed  to  them 
after  it  is  withheld  for  a  week  or  longer,  and  a  large  quantity  of 
water  is  taken  soon  afterwards.  Slop  containing  alkaline  wash- 
ing powders  and  soaps  irritate  the  stomach  and  intestines  and 
cause  a  serious  inflammation. 

The  symptoms  are  loss  of  appetite,  restlessness  and  some- 
times colicky  pains.  The  hog  usually  wanders  off  by  itself,  acts 
dull,  grunts,  lies  down  in  a  quiet  place  or  stands  with  the  back 
arched  and  the  abdomen  held  tense.  Vomiting  commonly  occurs. 
Sometimes  the  animal  has  a  diarrhoea.  The  body  temperature 
may  be  above  normal. 

The  treatment  consists  in  avoiding  irritating  feeds  and  sud- 
den changes  in  the  kind  or  (piantity  of  feed  fed.  Drenching  with 
hot  water,  or  with  about  one  ounce  of  ipecacuan  may  be  prac- 
tised. From  one  to  three  ounces  of  castor  oil,  depending  on 
the  size  of  the  hog,  may  be  given.  After  recovery  the  hogs 
should  be  confined  in  a  comfortable  pen  and  fed  an  easily  digested 
ration. 


DISEASES  OF  THE  DIGESTIVE  SYSTEM 


39 


DISEASES   OF   THE   IXTESTINES 

General  Discussion.— The  intestinal  tract  of  solipeds  is  the 
best  developed  of  any  of  the  domestic  animals  (Fig.  14).  It 
is  divided  into  two  ])ortions, 
smdll  and  large.  The  .small  in- 
testine is  a  little  over  seventy 
feet  in  length  and  abont  one 
and  one-half  inches  in  diameter. 
The  nmcous  membrane  lining 
presents  a  large  absorbing  sur- 
face and  is  well  snp]ilicd  with 


absorbing  vessels  that  take  np 
the  sngars,  proteids  and  fats, 
which  are  finally  distributed  to 
the  body  cells  by  the  blood  capil- 
laries. In  addition  to  these 
absorbing  vessels  the  mncons 
membrane  contains  intestinal 
glands  that  secrete  the  intesti- 
nal juice.  Other  digestive  se- 
cretions from  the  pancreatic 
gland  and  the  liver  are  poured 
into  the  small  intestine  near  its 
origin.  These  digestive  juices 
act  on  the  proteids,  sugars, 
starches  and  fats,  changing 
them  into  substances  that  are 
capable  of  being  absorbed. 

After  disengaging  itself  from 
the  mass  of  loops  lodged  in  the 
region  of  the  left  flank,  the  small  intestine  crosses  to  the  region 
of  the  right  flank,  where  it  terminates  in  the  first  division  of  the 
large  intestine. 

The  large  intestine  is  formed  by  the  following  divisions: 


Fig.  14. — Fnotograph  of  model  of  di- 
gestive tract  of  horse  :  (C)  oesophagus  ; 
(B,  D)  stomach;  (F)  liver;  (E,  G.  H)  small 
intestine;  (I  to  W)  large  intestine;  (A) 
spleen. 


40  NON-SPECIFIC  OR  GENERAL  DISEASES 

caecum,  double  colon,  floating  colon  and  rectum.  The  caecum 
is  a  large  blind  pouch  that  has  a  capacity  of  about  seven  gallons. 
The  double  colon  is  the  largest  division  of  the  intestines.  It  is 
about  twelve  feet  in  length  and  has  a  capacity  of  about  eighteen 
gallons.  This  portion  of  the  intestine  terminates  in  the  region 
of  the  left  flank  in  the  floating  colon.  The  latter  is  about  ten 
feet  in  length  and  about  twice  the  diameter  of  the  small  intestine, 
from  which  it  can  readily  be  distinguished  by  its  sacculated  walls. 
The  rectum  is  the  terminal  portion  of  the  intestinal  tract.  It 
is  about  one  and  one-half  feet  in  length  and  possesses  heavy, 
elastic  walls. 

Fermentation  and  cellulose  digestion  occur  in  the  cnecum 
and  double  colon.  It  is  in  the  floating  colon  that  the  faeces  are 
moulded  into  balls.  The  ficces  are  retained  in  the  rectum  until 
defecation  takes  place. 

The  intestinal  trad  of  cattle  is  longer  than  that  of  soli- 
peds  and  the  diflerent  divisions  are  not  as  well  defined  as  in  the 
horse's  intestine  and  about  one-half  its  diameter.  The  large 
intestine  is  about  thirty-five  feet  in  length  and  its  capacity  six 
or  seven  gallons  (Fig.  15). 

Acute  Intestinal  Indigestion  of  Solipeds. — Acute  indiges- 
tion is  more  common  in  horses  and  mules  than  it  is  in  any  of  the 
other  domestic  animals.  Because  of  the  difference  in  the  causes 
and  symptoms  manifested,  we  may  divide  it  into  the  following 
forms :  spasmodic,  flatulent  and  obstruction  colic. 

The  predisposing  causes  are  general  and  digestive  debility 
resulting  from  the  feeding  of  an  insufllcient  or  unsuitable  ration, 
and  general  and  parasitic  diseases  of  the  intestine.  Nervous, 
well-bred  horses  are  most  susceptible  to  nervous  or  spasmodic 
colic. 

The  direct  causes  are  improper  methods  of  feeding  and  water- 
ing; giving  the  animal  severe  or  unusual  exercise  immediately 
before  or  after  feeding;  the  feeding  of  spoiled  or  green  feeds  and 
new  grains ;  chilling  of  the  body ;  imperfect  mastication  of  feed 


DISEASES  OF  THE  DIGESTIVE  SYSTEM 


41 


because  of  defective  teeth  ;  obstruct  ion  of  the  intestine  by  worms. 
The  feeding  of  grain  at  a  time  when  the  animal  is  not  in  fit 
condition  to  digest  it  results 
in  imperfect  digestion  in 
both  the  stomach  and  intes- 
tine. This  leads  to  irritation 
of  the  intestine  and  abnor- 
mal fermentation  of  its  con- 
tents. The  drinking  of  a 
large  quantity  of  water  im- 
mediately after  feeding  grain 
flushes  at  least  a  part  of  the 
undigested  grain  from  the 
stonuich  through  the  small 
intestine  and  into  the  cic- 
cum.  New  grains,  such  as 
new  oats,  are  hurried  along 
the  small  intestine  and  reach 
the  large  intestine  practically 
undigested.  The  two  latter 
conditions  are  common  causes 
of  flatulent  or  wind  colic. 
Sudden  change  in  the  ration, 
especially  to  a  green  feed, 
may  result  in  intestinal  irri- 
tation and  flatulence. 


Horses    that    are    greedy 


Fig.  15.  —  Photograph  of  model  of  diges- 
tive tract  of  ruminant:  (C)  oesophagus;  (A) 
rumen;  (V)  reticulum;  (B)  omasum;  (N)  aboma- 
sum;  (D,  R,  I)  small  intestine;  and  (G,  F,  K,J) 
large  intestine. 


feeders  and  have  sharp,  un- 
even, smooth  or  diseased  teeth 
are  unable  to  masticate  the 
feed  properly.  This  results  in  unthriftiness  caused  by  imperfect 
digestion  and  assimilation  of  the  feed.  Such  animals  usually 
suffer  from  a  catarrhal  or  chronic  inflammation  of  the  intestine, 
and  may  have  periodic  attacks  of  acute  indigestion  or  colic. 


42 


NON-SPECIFIC  OR  GENERAL  DISEASES 


Obstruction  colic  is  very  often  caused  by  the  feeding  of  too 
much  roughage  in  the  form  of  straw,  shredded  fodder,  or  hay. 
Debility  often  contributes  to  this  form  of  indigestion,  and 
the  double  colon  may  become  badly  impacted  with  alimentary 
matter. 

Worms  may  irritate  the  intestinal  mucous  membrane  and 
interfere  with  digestion,  obstruct  the  intestine  and  cause  debility 
and  circulatory  disturbances.  The  large  round  worm  may  form 
a  tangled  mass  and  completely  fill  a  portion  of  the  double  colon. 


Fig.   16. — A  yearling  colt  that  died  ot  iiueunsm  colic. 

Some  species  attach  themselves  to  the  intestinal  wall,  suck  the 
blood  of  the  host  and  cause  amrmia  and  debility.  Colic  resulting 
from  circulatory  disturhances  is  not  common.  The  female  of 
a  certain  species  of  sclerostomw  deposits  eggs  in  the  mucous 
membrane.  On  hatching,  the  larvae  may  enter  a  blood  capillary, 
drift  along  in  the  blood  stream  and  finally  come  to  rest  in  a 
large  blood-vessel  that  supplies  a  certain  portion  of  the  intestines 
with  blood.  Here  the  parasite  develops.  The  wall  of  the  vessel 
becomes  irritated  and  inflamed,  pieces  of  fibrin  flake  off  and 
drift  along  the  blood  stream  until  finally  a  vessel  too  small  for 


DISEASES  OF  THE  DIGESTIVE  SYSTEM  43 

the  floating  particle  to  pass  through  is  reached  and  the  vessel 
becomes  j^higged.  The  loop  of  intestine  supplied  by  it  receives 
no  blood.  A  temporary  paralysis  of  the  loop  occurs,  which  per- 
sists imtil  a  second  vessel  is  able  to  take  over  the  function  of  the 
one  that  is  plugged.  This  form  of  colic  is  most  common  in  old 
horses  (Fig.  16). 

Such  complications  of  acute  indigestion  as  twisting,  infolding 
and  displacement  of  the  intestine  may  occur.  It  is  not  uncom- 
mon for  a  stallion  to  suffer  from  strangulated  hernia,  due  to  a 
rather  large  internal  inguinal  ring  and  a  loop  of  the  intestine 
passing  through  it  and  into  the  inguinal  canal  or  scrotum.  Such 
displacements  are  usually  accompanied  by  severe  colicky  pains. 

The  symptoms  vary  in  the  different  cases.  In  the  mild  form, 
the  colicky  pains  are  not  prominent,  but  in  the  acute  form,  the 
animal  is  restless,  getting  up  and  do^\^l  in  the  stall  and  rolling 
over.  These  movements  are  especially  marked  when  the  abdom- 
inal pain  is  severe. 

In  the  spasmodic  form  the  attack  comes  on  suddenly,  the 
colicky  pains  are  severe,  and  the  peristaltic  movement  of  the  intes- 
tine is  marked  and  accompanied  by  loud  intestinal  sounds.  In 
most  cases  of  indigestion  characterized  by  fermentation  and  col- 
lections of  gas  in  the  intestine  there  is  gastric  tympany  as  well. 

Acute  indigestion  characterized  by  impaction  of  the  large 
intestine  pursues  a  longer  course  than  the  forms  just  mentioned, 
and  the  abdominal  pain  is  not  severe. 

Congestion  and  inflammation  of  the  intestine  may  result 
from  the  irritation  produced  by  the  feed.  When  this  occurs,  the 
abdominal  pain  is  less  violent.  The  animal  usually  acts  dull, 
the  walk  is  slow  and  unsteady,  and  the  respirations  and  pulse 
beats  may  be  quickened. 

A  large  percentage  of  the  cases  of  acute  indigestion  terminate 
fatally.  The  course  of  the  disease  varies  from  a  few  hours  to 
several  days. 

The  treatment  is  both  preventive  and  curative.     The  preven- 


M  NON-SPECIFIC  OR  GENERAL  DISEASES 

tive  treatment  is  by  far  the  most  important.  This  consists  in 
observing  right  methods  of  feeding  and  caring  for  horses.  The 
attendant  should  note  the  condition  of  the  animal  before  feeding 
grain,  feed  regularly  and  avoid  sudden  changes  in  feed.  If  a 
horse  has  received  unusual  exercise,  it  is  proper  to  feed  hay 
first,  and  when  the  animal  is  cooled  out,  water  and  feed  grain. 
Drinking  a  small  quantity  of  water  when  tired  or  following 
a  meal  is  not  injurious,  but  a  large  quantity  of  water  taken  at 
such  times  is  injurious  and  dangerous  to  the  health  of  the  animal. 
The  feeding  of  spoiled  or  mouldy  feeds  to  horses  is  highly 
injurious. 

The  horse  should  be  given  a  roomy,  comfortable  stall  that  is 
well  bedded,  or  a  clean  grass  lot.  If  the  attack  appears  when  the 
animal  is  in  harness,  we  should  stop  working  it  and  remove  the 
harness  immediately.  Work  or  exercise  usually  aggravates  the 
case  and  may  cause  congestion  and  inflammation  of  important 
body  organs.  In  cold  weather  the  animal  should  be  protected 
by  blankets.  If  the  pain  is  violent,  sedatives  may  be  given.  The 
gaseous  disturbances  should  be  relieved  by  puncturing  the  wall 
of  the  intestine  with  the  trocar  and  cannula.  Rectal  injections 
of  cold  water  may  be  resorted  to.  Fluid  extract  of  cannabis 
indica  in  quarter  ounce  doses  and  repeated  in  one  hour  may  be 
given  in  linseed  oil.  In  all  cases  it  is  advisable  to  drench  the 
animal  with  one  pint  of  raw  linseed  oil  and  two  ounces  of  turpen- 
tine. Strychnine,  eserine  and  pilocarpine  are  the  drugs  com- 
monly used  by  the  veterinarians  in  the  treatment  of  acute  indi- 
gestion. Small  and  repeated  doses  of  the  above  drugs  are  pre- 
ferred to  large  doses.  This  is  one  of  the  diseases  that  requires 
prompt  and  skilled  attention. 

Sharp,  uneven  or  diseased  teeth  should  receive  the  necessary 
attention.  In  old  horses,  chopped  hay  or  ground  feeds  should 
be  fed  when  necessary.  Debility  resulting  from  hard  work, 
wrong  methods  of  feeding  and  intestinal  disorders  must  be  cor- 
rected before  the  periodic  attacks  of  indigestion  can  be  relieved. 


DISEASES  OF  THE  DIGESTIVE  SYSTEM  45 

If  the  presence  of  intestinal  worms  is  suspected,  the  necessary 
treatment  for  ridding  the  animal  of  these  parasites  should  be 
resorted  to. 

Bitter  or  saline  tonics  should  be  administered  in  the  feed 
when  necessary.  The  followini;;  formula  is  useful  as  a  digestive 
tonic :  sodium  bicarbonate  and  sodium  sulfate,  one  pound  of 
each,  powdered  gentian  one-half  pound,  and  oil  meal  five  pounds. 
A  small  handful  of  this  mixture  may  be  given  with  the  feed  two 
or  three  times  daily. 

Inflammation  of  the  Intestines. — The  same  causes  mentioned 
in  inflammation  of  the  stomach  and  acute  indigestion  may  cause 
this  disease.  It  is  most  frequent  at  times  when  there  are  gi'eat 
variations  in  the  temperature.  Sudden  cold  or  any  influence 
that  chills  the  surface  of  the  body,  or  internal  cold  caused  by 
drinking  ice  water  or  eating  frozen  feed,  may  cause  it.  The 
infectious  forms  of  enteritis  are  caused  by  germs  and  ptomaines 
in  the  feed.  Drinking  filthy  water  or  eating  spoiled,  mouldy 
feeds  are  common  causes.  In  cattle  pasturing  in  low,  marshy 
places,  enteritis  may  be  common.  The  toxic  form  is  caused  by 
irritating  jDoisons,  such  as  caustic  acids,  alkalies  and  meat  brine. 

In  the  mild  form  of  enteritis  the  appetite  is  irregular,  the 
animal  acts  dull  and  stupid  and  may  be  noticed  lying  do\\m  more 
than  common.  Slight  abdominal  pains  occur,  especially  follow- 
ing a  meal.  An  elevation  in  the  body  temperature  may  be  noted 
and  the  animal  may  drink  more  water  than  usual.  Constipation 
or  a  slight  diarrhnoa  may  be  present.  The  firces  may  be  soft  and 
foul  smelling,  coated  with  mucus,  and  slightly  discolored  with 
blood. 

In  the  severe  form  of  enteritis  pressure  on  the  abdomen  may 
cause  pain,  the  respiration  and  pulse  beats  are  quickened  and 
the  body  temperature  is  elevated.  The  abdominal  pain  may  be 
severe  and  the  animal  is  greatly  depressed  or  acts  dull.  The 
movement  of  the  intestines  is  suppressed  at  first  and  constipation 
occurs.     Fermentation  and  the  formation  of  gas  may  take  place. 


46  NON-SPECIFIC  OR  GENERAL  DISEASES 

Later  the  intestinal  peristalsis  increases  and  a  fonl-smelling 
diarrhoea  sets  in  that  is  often  mixed  with  hlood.  In  the  toxic 
form  there  may  he  marked  nervons  symptoms.  Spasms,  convul- 
sions, stupefaction  and  coma  may  be  manifested. 

In  the  mild  form  recovery  usually  occurs  within  a  few  days. 
The  more  serious  forms  of  the  disease  do  not  terminate  so  favor- 
ably.   In  the  toxic  form  death  usually  occurs  within  a  few  days. 

The  large  majority  of  cases  of  enteritis  can  be  prevented  by 
practising  the  necessary  preventive  measures.  It  is  very  neces- 
sary that  animals  exposed  to  cold  be  provided  with  dry  sleeping 
quarters  that  are  free  from  draughts.  Where  a  number  of  ani- 
mals are  fed  a  heavy  grain  ration,  or  fed  from  the  same  trough, 
they  should  be  kept  under  close  observation.  This  is  necessary 
in  order  to  detect  cases  of  indigestion  or  overfeeding  early,  and 
resort  to  the  necessary  lines  of  treatment,  so  as  to  prevent  further 
irritation  to  the  intestinal  tract.  Live  stock  should  not  be  forced 
to  drink  water  that  is  ice-cold.  Low,  poorly-drained  land  is  not 
a  safe  pasture  for  cattle  and  horses.  Spoiled  roots,  grains  and 
silage,  mouldy,  dirty  roughage  and  decomposed  slops  should  not 
be  fed  to  live  stock. 

The  treatment  consists  in  withholding  all  feed  and  giving  the 
animal  comfortable,  quiet  quarters — warm  quarters  and  pro- 
tection from  the  cold,  ]3i"<Jviding  the  animal  with  a  heavy  straw 
bed,  or  with  blankets  if  necessary,  if  the  weather  is  cold.  From 
five  to  forty  grains  of  calomel  may  be  given,  depending  upon  the 
size  of  the  animal  and  the  frequency  of  the  dose,  two  or  three 
times  a  day.  In  case  the  animal  is  suffering  severe  pain,  mor- 
phine given  hypodermically  may  be  indicated.  In  the  mild  form 
and  at  the  very  beginning  of  the  attack,  linseed  oil  may  be 
administered  to  the  larger  animals.  The  dose  is  about  one  quart. 
The  smaller  animals  may  be  given  castor  oil  in  from  one-  to  four- 
ounce  doses. 

When  convalescence  is  reached  the  animal  should  be  fed 


DISEASES  OF  THE  DIGESTIVE  SYSTExM  47 

very  carefully,  as  the  diirestive  tract  is  not  in  condition  to  digest 
heavy  rations  or  feeds  that  ferment  readily. 

Diarrhoea. —  Diarrhcca  occnrs  as  a  symptom  of  irritation  and 
inflammation  of  the  intestinal  mucous  membrane.  Sudden 
changes  in  the  feed,  the  feeding  of  a  succulent  green  ration, 
severe  exercise  when  the  animal  is  not  in  condition  for  it,  and 
chronic  indigestion  may  cause  diarrhcra  in  the  absence  of  an 
intestinal  inflammation. 

The  following  symptoms  may  be  noted  :  Animals  aliected  by  a 
diarrhoea  act  dull  and  weak ;  thirst  is  increased  and  the  animal 
may  show  evidence  of  fever ;  the  intestinal  evacuations  are  soft, 
thin,  and  sometimes  have  an  offensive  odor.  If  the  diarrha?a  con- 
tinues for  several  days,  the  animal  loses  flesh  rapidly  and  the 
appetite  is  irregular.  In  such  cases  Aveakness  is  a  prominent 
symptom. 

Recovery  usually  occurs  when  the  animal  is  dieted  and  rested. 

The  treatment  consists  in  giving  a  physic  of  linseed  or  castor 
oil.  Horses  and  cattle  may  be  given  from  one-half  to  one  (juart 
of  linseed  oil ;  sheep  and  hogs  from  one  to  four  ounces  of 
castor  oil.  Feed  should  be  withheld.  Morphine  may  be  given 
hypodermically  to  the  large  animals  after  a  period  of  six  to  eight 
hours  following  the  administration  of  the  physic. 

The  following  formula  is  quite  useful  in  checking  diarrhcea: 
salol  one-half  ounce,  bismuth  subnitrate  one  ounce,  and  bicar- 
bonate of  soda  two  ounces.  The  dose  of  this  mixture  is  from  one 
to  four  drachms,  depending  on  the  size  of  the  animal,  three  or 
four  times  a  day. 

White  Scours  or  Diarrhoea  in  Young  Animals. — Young 
animals,  when  nursing  the  mother  or  fed  by  liand,  frequently 
develop  congestion  and  inflammation  of  the  stomach  and  intes- 
tines.    This  disorder  is  characterized  by  a  diarrhoea. 

The  causes  may  be  grouped  under  two  heads :  wrong  methods 
of  feeding  and  care,  and  specific  infection. 

The  first  milk  of  the  mother  is  a  natural  laxative  and  aids 


48  NON-SPECIFIC  OR  GENERAL  DISEASES 

in  ridding  the  intestine  of  the  voung  of  snch  waste  material 
(meconium)  as  collects  during  fetal  life.  If  this  milk  is  with- 
held, the  intestine  becomes  irritated,  constipation  occurs,  fol- 
lowed by  a  diarrh(pa  or  serious  s^aiiptoms  of  a  nervous  character, 
caused  by  the  poisonous  effect  of  the  toxic  substances  absorbed 
from  the  intestine  on  the  nervous  system. 

Changes  in  the  ration  fed  the  mother,  excitement,  unusual 
exercise  and  disease  change  the  composition  of  the  mother's 
milk.  Such  milk  is  irritating  to  the  stomach  and  intestines  of 
the  young.  This  irritation  does  not  always  develop  into  a  diar- 
rhoea, but  may  result  in  a  congestion  of  the  stomach. 

When  the  young  are  raised  artificially  or  by  hand,  and  fed 
milk  from  different  mothers  of  the  same  or  different  species,  or 
changed  from  whole  to  skim  milk,  acute  and  chronic  digestive 
disorders  that  are  accompanied  by  a  diarrhcea  are  common. 
Feeding  calves  from  filthy  pails,  allowing  them  to  drink  too 
rapidly  and  giving  them  fermented  milk  are  common  causes  of 
scours. 

White  scours  caused  by  irritating  germs  is  a  highly  infectious 
disease.  The  disease-producing  germs  gain  entrance  to  the  body 
by  way  of  the  digestive  tract  and  the  umbilical  cord. 

Insanitary  conditions,  such  as  dark,  cold,  damp,  filthy  quar- 
ters, lower  the  vitality  of  young  animals,  and  predispose  them  to 
digestive  disorders  as  well  as  other  diseases. 

The  symploiiis  are  as  follows :  Constipation  accompanied  by 
a  feverish  condition  precedes  the  diarrhoea;  colicky  pains  are 
sometimes  manifested ;  the  diarrha'a  is  usually  accompanied  by 
depression,  falling  oft"  in  appetite  and  weakness.  At  first  the 
intestinal  discharges  are  not  very  foul  smelling;  later  the 
odor  is  very  disagreeable.  The  faeces  may  be  made  up  largely 
of  undigested,  decomposed  milk  that  adheres  to  the  tail  and 
hind  parts.  If  the  diarrhoea  is  severe,  the  animal  refuses  to 
suckle  or  drink  from  the  pail,  and  loses  flesh  rapidly.  It  is 
usually  found  lying  dowai.     The  ears  droop  and  the  depression 


DISEASES  OF  THE  DIGESTIVE  SYSTEM  49 

is  marked.    The  body  temperature  may  vary  from  several  degrees 
above  to  below  the  average  normal. 

The  infectious  form  of  white  scours  may  be  diagnosed  l)v  the 
history  of  the  outbreak.  In  this  form  of  the  disease,  a  largo 
percentage  of  the  yonng  are  affected  and  the  death-rate  is  very 
high. 

Calves  and  lambs  frequently  die  of  an  acute  congestion  of 
the  fourth  stomach.  In  this  disease,  the  symptoms  appear  shortly 
after  feeding.  It  is  characterized  by  colicky  pains,  convulsions 
and  coma. 

Tlie  treatment  is  largely  preventive.  Young  animals  should 
be  provided  with  dry,  clean,  well-ventilated  quarters  and  allowed 
plenty  of  exercise.  Colts  thrive  best  if  alloAved  to  run  in  a  blue 
grass  pasture  with  the  mother.  If  the  mother  is  worked,  suitable 
provisions  in  the  way  of  quarters  and  frequent  nursing  should 
be  provided.  Calves,  lambs  and  pigs  are  the  most  frequent 
sufferers  from  insanitary  quarters.  In  breeding,  we  should 
always  strive  to  get  strong,  vigorous,  healthy  young.  The  care 
given  the  mother  in  the  way  of  exercise  and  feeding  is  an  im- 
portant factor  here. 

The  first  milk  of  the  mother  should  not  be  withheld  from  the 
young,  especially  if  the  animal  is  raised  by  hand.  We  must 
also  feed  it  regularly  and  not  too  much  at  any  one  time.  Any 
change  in  the  milk  should  be  made  gradually,  and  it  is  usually 
advisable  to  reduce  the  ration  slightly  \vhen  such  a  change  is 
made,  so  as  not  to  overwork  the  digestive  organs.  Pails  and 
bottles  from  which  the  animal  feeds  should  be  kept  clean. 

Colts  raised  on  cow's  milk  must  be  fed  and  cared  for  care- 
fully. The  milk  must  be  sweet  and  made  more  digestible  by 
diluting  it  with  one-third  water.  A  little  sugar  may  be  added. 
It  is  very  advisable  to  add  from  one-half  to  one  ounce  of  lime 
water  to  each  pint  of  milk  fed.  Frequent  feeding  is  very  neces- 
sary at  first,  and  we  must  not  underestimate  the  quantity  of 
4 


50  NON-SPECIFIC  OR  GENERAL  DISEASES 

milk  necessary  to  keep  the  colt  in  good  condition.     It  slionld  be 
taught  to  eat  grain  as  soon  as  possible. 

Because  of  the  irritated  condition  of  the  stomach  and  intes- 
tine, the  animal  suffering  from  diarrhoea  is  unable  to  digest  its 
feed.  For  this  reason  it  is  very  important  to  withhold  all  feed 
for  at  least  twelve  hours.  Water  should  be  provided.  The  ali- 
mentary tract  is  relieved  of  the  irritating  material  by  giving 
the  animal  a  physic  of  castor  or  linseed  oil.  The  dose  varies 
from  one-quarter  to  one-half  ounce  for  the  lamb  and  from  one 
to  four  ounces  for  the  colt  or  calf.  It  is  advisable  in  most  cases 
to  follow  this  with  the  following  mixture:  l)i('arl)onate  of  soda 
one  ounce,  bismuth  subnitrate  one-half  ounce,  and  salol  one- 
quarter  ounce.  The  dose  for  the  colt  and  calf  is  one  teaspoonful 
three  times  a  day.  Lambs  and  pigs  may  be  given  from  one- 
fourth  to  one-half  the  above  dose. 

It  is  usually  advisable  to  give  ewes  and  sows  a  physic  if 
their  young  develop  a  diarrhoea.  ]\rothers  that  are  heavy  milkers 
may  be  given  a  physic  the  second  or  third  day  following  birth. 
The  ration  should  be  reduced  as  well  during  the  first  week. 

Infectious  white  scours  should  be  treated  as  an  infectious 
disease.  A  few  days  before  giving  birth  to  the  young,  the 
mother  should  be  moved  to  new  quarters ;  a  pasture  or  lot  that 
has  not  been  in  use,  or  a  clean,  disinfected  stall  or  stable.  In 
addition  to  these  preventive  measures,  soon  after  birth  the  young 
animal  should  be  vaccinated  with  white  scour  serum, 

DISEASES  OF  TTTE  DIGESTIVE  TRACT  OF  rOULTRY 

General  Discussion. — The  digestive  tract  of  poultry  is  com- 
posed of  the  following  organs :  mouth,  gullet,  crop,  stomach,  giz- 
zard and  intestines,  with  the  two  large  glands,  the  liver  and 
pancreas.  The  digestion  of  the  feed  begins  in  the  crop.  Here 
the  feed  is  held  for  a  short  time,  mixed  with  certain  fluids  and 
softened.     On  reaching  the  stomach  it  becomes  mixed  with  the 


DISEASES  OF  THE  DIGESTI\T]:  SYSTEM  51 

digestive  fluid  secreted  by  the  gastric  glands.  This  second 
digestive  action  consists  in  thoroughly  soaking  the  feed  in  the 
gastric  juice,  making  it  soft  and  preparing  it  for  maceration  by 
the  heavily  muscled  gizzard.  Following  maceration  it  passes  into 
the  intestine.  It  is  here  that  the  digestive  action  is  completed 
and  absorption  occurs. 

Under  the  conditions  of  domestication,  poultry  are  subject 
to  a  great  variety  of  intestinal  disorders. 

Diseases  of  the  Crop. — Impaction  and  inflammation  are  the 
two  conniion  diseases  of  the  crop.  Large,  impacted  crops  are 
usually  caused  by  the  feeding  of  too  much  dry  feed,  fermentation 
of  the  contents  of  the  crop  and  foreign  bodies  that  obstruct  the 
opening  from  the  organ. 

Inflammation  of  the  crop  is  caused  by  excessive  use  of  condi- 
ments in  the  feed,  putrid  or  spoiled  feeds  and  eating  caustic 
drugs,  such  as  lime  and  rat  poison. 

The  symptoms  are  dulness,  an  indisposition  to  move  about, 
drooping  wings  and  efforts  to  eject  gases  and  liquids.  The  crop 
is  found  greatly  distended  and  either  hard  or  soft,  depending  on 
the  quantity  of  feed  present  and  the  cause  of  the  distention. 
If  fermentation  is  present  the  crop  usually  feels  soft. 

The  preventive  treatment  consists  in  practising  proper 
methods  of  feeding.  The  curative  treatment  of  a  recent  case 
consists  in  manipulating  the  mass  of  feed,  breaking  it  up  and 
forcing  it  upwards  toward  the  mouth.  If  difticulty  in  breaking 
up  the  mass  is  experienced,  it  is  advisable  to  administer  a  table- 
spoonful  of  castor  oil  to  the  bird. 

If  the  above  manipulations  are  unsuccessful,  an  operation  is 
necessary.  This  consists  in  making  an  opening  through  the  skin 
and  the  wall  of  the  crop  and  removing  the  contents  with  tweezers. 
The  opening  must  be  closed  with  sutures.  The  proper  aseptic 
precautions  must  be  observed. 

In  inflammation  of  the  crop,  the  bird  should  be  dieted  for  at 
least  one  day,  and  one  teaspoonful  of  castor  oil  given  as  a  laxative. 


52  NON-SPECIFIC  OR  GENERAL  DISEASES 


* 


Acute  and  Chronic  Indigestion. — The  recognition  of  special 
forms  of  indigestion  in  poultry  is  difficult.  A  flock  of  poultry 
that  is  subject  to  careless  and  indifferent  care  may  not  thrive  and 
a  number  of  the  birds  develop  digestive  disorders.  This  may  be 
indicated  by  an  abnormal  or  depraved  appetite  and  emaciated 
condition.  Constipation  or  diarrhoea  may  occur.  In  the  more 
severe  cases  the  bird  acts  dull,  the  feathers  are  ruffled  and  it 
moves  about  very- little. 

TJie  trcaiment  consists  in  removing  the  cause,  and  giving  the 
flock  a  tonic  mixture  in  the  feed.  The  following  mixture  may  be 
used:  powdered  gentian  and  powdered  ginger,  eight  ounces  of 
each,  Glauber's  salt  four  ounces,  and  sulfate  of  iron  two  ounces. 
One  ounce  of  the  above  mixture  may  be  given  in  ten  pounds 
of  feed. 

White  Diarrhoea  of  Young  Chickens. — White  diarrhoea  is 
of  the  greatest  economic  importance  to  the  poultryman.  The 
loss  of  chicks  from  this  disease  is  greater  than  the  combined  loss 
resulting  from  all  other  diseases.  It  is  stated  by  some  authors 
that  not  less  than  fifty  per  cent  of  the  chickens  hatched  die  from 
white  diarrhoea. 

Such  a  heavy  death-rate  as  is  attributed  to  this  disease  can 
not  result  from  improper  methods  of  handling  and  insanitary 
conditions.  Before  it  was  proved  that  white  diarrhoea  was  caused 
by  specific  germs,  a  great  deal  of  emphasis  was  placed  on  such 
causes  as  debilitated  breeding  stock,  improper  incubation,  poorly 
ventilated,  overcrowded  brooders,  too  high  or  too  low  tempera- 
tures and  filth.  Such  conditions  are  important  predisposing 
factors,  and  may,  in  isolated  cases,  result  in  serious  intestinal 
disorders. 

The  microorganisms  causing  this  disease  belong  to  both  the 
plant  and  animal  kingdoms.  Infection  usually  occurs  within 
a  day  or  two  following  hatching.  Chicks  two  or  three  weeks  of 
age  seldom  develop  the  acute  form  of  the  disease.  Incubator 
chicks  are  the  most  susceptible  to  the  disorder. 


DISEASES  OF  THE  DIGESTIVE  SYSTEM  53 

The  following  symptoms  occur:  The  chicks  present  a  droopy, 
sleepy  appearance;  the  eyes  are  closed,  and  the  chicks  huddle 
together  and  peep  much  of  the  time ;  the  whitish  intestinal  dis- 
charge is  noticed  adhering  to  the  fluft'  near  the  margins  of  the 
vent,  and  the  young  bird  is  very  weak;  death  may  occur  within 
the  first  few  days.  After  the  first  two  weeks  the  disease  becomes 
less  acute.  In  the  highly  acute  form  the  chicks  die  without  show- 
ing the  usual  train  of  symptoms. 

It  is  very  easy  to  differentiate  between  the  infectious  and 
the  non-infectious  diarrhoea.  In  the  latter,  the  percentage  of 
chicks  affected  is  small  and  the  disease  responds  to  treatment 
more  readily  than  does  the  infectious  form.  The  death-rate  in 
the  latter  form  is  about  eighty  per  cent. 

The  onlv  method  of  recogiiizing  white  diarrhoea  infection 
in  laying  hens  is  by  means  of  the  agglutination  test.  Most  state 
veterinary  laboratories  are  equipped  to  make  this  test. 

The  treatment  of  diarrhoea  in  chicks  from  any  cause  is  pre- 
ventive. This  consists  in  removing  the  cause.  Xo  person  can 
successfully  handle  poultry  if  he  does  not  give  the  necessary 
attention  to  sanitation.  Poultry  houses,  runs,  watering  foun- 
tains and  feeding  places  must  be  constantly  cleaned  and  disin- 
fected. The  degree  of  attention  necessary  depends  on  the  sur- 
roundings, the  crowded  condition  of  the  poultry  houses  and  runs, 
and  the  presence  of  disease  in  the  flock.  If  disease  is  present, 
we  can  not  clean  and  disinfect  the  quarters  too  often.  The  attend- 
ant can  not  overlook  details  in  handling  the  incubator  or  brooder 
and  feeding  the  chicks  and  be  uniformly  successful. 

If  the  disease  is  known  to  be  present  in  the  flock,  the  incu- 
bators and  brooders  should  be  thoroughly  disinfected  by  fumi- 
gating them  with  formaldehyde  gas.  If  dirty,  they  should  first 
be  washed  with  a  water  solution  of  a  good  disinfectant.  For  a 
period  of  from  twenty-four  to  forty-eight  hours  after  hatching, 
the  chicks  should  receive  no  feed.  Dr.  Kaupp  recommends  as  an 
intestinal  antiseptic,  sulfocarbolate  thirty  grains,  bichloride  of 


54  NON-SPECIFIC  OR  GENERAL  DISEASES 

mercury  six  grains,  and  citric  acid  three  grains,  dissolved  in 

one  gallon  of  water.     This  solution  should  be  kept  in  front  of 

the  chicks  all  the  time.     A  water  solution  of  powdered  copper 

sulfate  (about  one-half  teaspoonful  dissolved  in  one  gallon  of 

water)  may  be  used. 

Hens  reacting  to  the  agglutination  test  for  bacillary  white 

diarrhoea  should  be  removed  from  the  flock.     This  is  the  most 

important  control  measure  to  practice  in  ridding  the  flock  of 

this  disease. 

QUESTIONS 

1.  Name  the  organs  that  form  the  digestive  apparatus. 

2.  What  digestive  action  on  the  feed  occurs  in  the  mouth  ? 

3.  Describe  the  causes  and  symptoms  of  inllammation  of  the  moutli :   de- 

scribe the  treatment. 

4.  Give  the  causes  for  depraved  appetite;  describe  the  symptoms  and  treat- 

ment. 

5.  Give  the  capacity  of  the  horse's  stomach. 

6.  Name  the  different  compartments  of  the  ruminant's  stomach. 

7.  Give  the  capacity  of  the  stomach  of  ruminants. 

8.  Name  the  different  stages  of  digestion  occurring  in  the  stomach  of  the 

hog. 

9.  What  forms  of  acute  indigestion  involve  the  stomach  of  solipeds?     Give 

causes  and  treatment. 

10.  Give  the  causes  of  indigestion  of  the  stomach  of  ruminants. 

11.  Give  the  treatment  for  the  different  forms  of  indigestion  of  the  stomach 

of  ruminants. 

12.  Name  the  divisions  of  small  and  large  intestines  of  solipeds  and  rumi- 

nants. 
1.3.  What  is  the  capacity   and  length   of  large  intestine   of   solipeds  and 
ruminants  ? 

14.  Wliat  are  the  different  forms   of  acute   indigestion  of  the  horse,   and 

causes? 

15.  Give  a  general  line  of  treatment  for  acute  indigestion  of  the  horse. 

IG.  Give  the  causes  of  wliite  diarrhoea  in  the  young  chicks;  give  a  line  of 
treatment. 

17,  Name  the  organs  of  the  digestive  apparatus  of  poultry. 

18.  Name  the  common  diseases  of  the  digestive  apparatus  of  poultry,  and 

give  the  causes. 


CHAPTER  V 

DISEASES   OF  THE  LIVER 

General  Discussion. — The  liver  is  one  of  the  most  important 
glands  of  the  body,  as  well  as  the  largest.  Because  of  its  physio- 
logical influence  over  the  functions  of  the  kidneys,  intestines, 
and  body  in  general  and  the  varied  functions  that  it  possesses, 
it  is  frequently  affected  by  functional  disorders. 

All  of  the  blood  that  comes  directly  from  the  intestine  is  re- 
ceived by  the  liver.  It  secretes  the  bile,  neutralizes  many  of  the 
poisonous  substances  and  end  products  of  digestion  that  are 
taken  up  by  the  absorbing  vessels  of  the  intestine,  and  acts  as 
a  storehouse  for  the  glycogen. 

It  can  be  readily  understood  from  this  brief  statement  of 
the  nature  of  the  liver  functions,  that  any  functional  disorder 
of  the  liver  may  be  far  reaching  in  its  effect.  In  many  of  the 
diseases  that  involve  other  organs,  the  liver  may  be  ^Ji'iniarily 
affected.  It  is  difficult  to  diagnose  functional  disorders  of  the 
liver  that  are  responsible  for  a  diseased  condition  of  some  other 
body  organ.  A  knowledge  of  the  physiology  and  pathology  of 
the  liver  is  of  the  greatest  importance  in  the  diagnosis  of  this 
class  of  disorders. 

In  the  larger  domestic  animals,  symptoms  of  liver  diseases 
are  more  obscure  than  in  the  small  animals.  In  certain  parasitic 
diseases  and  in  mixed  and  specific  infectious  diseases,  the  liver 
may  show  marked  pathological  changes. 

Common  Causes  of  Liver  Disorders. — Domestic  animals 
commonly  live  under  very  unnatural  conditions.  Ill  results 
do  not  follow  unless  these  conditions  are  so  extreme  as  to  violate 
practically  all  of  the  health  laws.  Pampered  animals  are  espe- 
cially prone  to  liver  disorders.  The  feeding  of  too  heavy  and 
too  concentrated  a  ration  together  with  insufficient  exercise  is 
one  of  the  most  common  causes  of  disorders  of  the  liver.     The 

55 


56  NON-SPECIFIC  OR  GENERAL  DISEASES 

feeding  of  a  ration  that  is  unsuitable  for  that  particular  species 
is  a  common  source  of  disease  in  animals.  For  example,  the 
feeding  to  carnivora  of  a  ration  made  up  largely  of  starchy- 
feed,  and  the  feeding  of  a  ration  containing  an  excessive 
quantity  of  j)rotein  to  herbivorous  animals  may  result  in  in- 
testinal, liver  and  nervous  disorders.  Spoiled  feed  may  prove 
highly  injurious.  Catarrhal  inflammation  of  the  intestine  and 
intestinal  parasites  may  obstruct  the  bile  duct,  and  interfere 
seriously  with  the  functions  of  the  liver. 

Sijmptoms, — In  diseases  of  the  liver  the  appetite  is  irregu- 
lar or  the  animal  refuses  to  eat,  is  constipated,  or  has  diarrhoea. 
The  fseces  may  be  grayish  colored  or  foul  smelling.  Colicky 
pains  are  sometimes  manifested.  Usually  the  animal  acts  dull 
and  weak.  A  raise  in  body  temperature  may  be  noted.  The 
visible  mucous  membranes  may  appear  yellowish-  or  brownish- 
red  in  color. 

Treatment. — Animals  grazing  over  well  drained  pastures 
that  are  free  from  injurious  weeds  and  provided  with  plenty 
of  drinking  water,  seldom  develop  diseases  of  the  liver.  Exer- 
cise, a  natural  diet  and  plenty  of  clean  water,  as  well  as  prevent- 
ing liver  disorders,  may  be  classed  among  the  most  important 
of  all  curative  agents.  Laxatives  or  cathartics,  such  as  oils, 
salts,  aloes,  and  calomel,  in  small  doses  may  be  given.  We  pre- 
fer the  administration  of  oil  or  aloes  to  horses,  Glauber's  or 
Epsom  salts  to  ruminants,  and  calomel  to  dogs.  The  adminis- 
tration of  minimum  doses  of  these  drugs,  and  repeating  the  dose 
after  a  short  interval,  is  preferable  to  large  doses.  Alkaline 
tonics  are  also  indicated.  The  following  mixture  may  be  given : 
bicarbonate  of  soda,  sulfate  of  soda  and  common  salt,  eight 
ounces  of  each,  and  powdered  gentian  and  sulfate  of  iron,  four 
ounces  of  each.  Large  animals  may  be  given  a  small  table- 
spoonful  of  this  mixture  with  the  feed  three  times  a  day.  The 
dose  for  sheep  and  hogs  is  one  teaspoonful.  A  very  light,  easily 
digested  ration  should  be  fed. 


DISEASES  OF  THE  LIVER  57 

QUESTIONS 

1.  What  can  be  said  of  the  importance  of  the  liver? 

2.  Tell  something  of   its  duties  as  a  gland. 

3.  In  what  animals  are  liver  troubles  most  conspicuous  when   present? 

4.  Give  causes  of  liver  disorders. 

5.  What  are  the  symptoms? 

6.  \Miat  are  the  most  important  natural  cures? 

7.  What  rule  may   be  given  for   adapting   suitable   laxatives   to  different 

classes  of  animals? 


CHAPTER  VI 
DISEASES    OF    THE    URINARY    ORGANS 

General  Discussion. — The  urinary  apparatus  is  composed 
of  two  glands,  the  kidneys  and  an  excretory  apparatus  that 
carries  the  excretion  of  the  kidneys  to  the  outside. 

The  kidneys  are  situated  in  the  superior  region  of  the 
abdominal  cavity  (sublumbar)  above  the  peritoneum,  and  to 
the  right  and  left  of  the  median  line.  They  are  highly  vascular 
glands,  somewhat  bean-shaped  and  of  a  deep  red  color.  These 
glands  are  capable  of  removing  from  the  blood  a  fluid  that  is 
essentially  difi^erent  in  composition  and  which,  if  retained  in 
the  blood,  would  be  harmful  or  poisonous  to  the  body  tissues. 

The  kidney  excretions  are  carried  from  the  pelvis  of  the 
kidneys  by  the  right  and  left  ureters.  These  canals  terminate 
in  the  bladder,  an  oval-shaped  reservoir  for  the  urine.  This 
organ  is  situated  in  the  posterior  portion  of  the  abdominal 
cavity  and  at  the  entrance  to  the  pelvic  cavity.  Posteriorly,  it 
forms  a  constricted  portion  or  neck.  It  is  here  that  the  urethra 
originates.  This  canal  represents  the  last  division  of  the  excre- 
tory apparatus.  In  the  female,  the  urethra  is  short  and  termi- 
nates in  the  vulva.  In  the  male  it  is  long  and  is  supported  by 
the  penis. 

The  urine  secreted  by  the  kidneys  is  a  body  excretion, 
and  consists  of  water,  organic  matter  and  salts.  The  nitrog- 
enous end-products,  aromatic  compounds,  coloring  matter,  and 
mucin  form  the  organic  matter.  The  nitrogenous  end-products 
and  aromatic  compounds  are  urea,  uric  and  hippuric  acids,  ben- 
zoic acid  and  ethereal  sulfates  of  phenol  and  cresol.  The  salts 
are  sulfates,  i)hosphates  and  chlorides  of  sodium,  potassium, 
calcium  and  magnesium.  The  organic  and  inorganic  matter 
varies  with  the  ration. 

The  quantity  of  urine  secreted  within  a  given  time  varies 
58 


DISEASES  OF  THE  URLNARY  ORGANS  59 

in  the  different  species  and  at  different  times  in  the  same 
individual.  In  the  horse  the  quantity  secreted  in  twenty-fonr 
honrs  varies  from  twelve  to  fifteen  pints ;  in  cattle  from  ten  to 
forty  pints;  in  sheep  from  one-half  to  one  and  three-quarter 
pints.  The  nonnal  color  of  the  urine  varies.  In  tlie  horse  it  is 
yellow  or  yellowish-red;  in  cattle  and  sheep  yellowish;  and  in 
the  dog-  a  straw  yellow.  The  specific  gravity  varies  with  the 
quantity  secreted  and  the  ration  fed.  When  the  quantity  of 
urine   secreted   is   above   the   average,    tlie   specific  gravity   is 

usually  low. 

The  Necessity  of  Examining  the  Urine. — In  diseases  of  the 
urinary  apparatus,  a  careful  examination  of  the  urine  is  very 
necessary  in  order  to  be  able  to  form  a  correct  diagnosis.  In 
domestic  animals  it  is  impractical  to  attempt  to  determine  the 
exact  amount  of  urine  passed  within  a  certain  time,  but  we  can 
make  a  general  estimate  of  the  quantity  passed  by  carefully 
observing  the  animal  and  noting  the  condition  of  the  bedding  in 
the  stall.  The  sample  of  urine  to  be  examined  is  best  taken 
from  urine  collected  at  different  periods  during  the  day.  We 
should  note  its  color  and  consistency.  The  different  substances 
in  the  urine  can  be  determined  only  by  determining  the  specific 
gravity,  testing  wnth  certain  chemical  reagents  and  by  making  a 
microscopic  examination  of  the  sediment.  Xormal  urine  from 
the  horse  may  be  turbid  or  cloudy  and  more  or  less  slimy, 
because  of  the  presence  of  mucin.  This  is  less  true  of  other 
species.  In  disease  the  color  of  the  urine  may  be  changed  to  a 
pale  yellow,  red  or  brown.  For  example,  in  congestion  of  the 
kidneys  the  urine  is  light  in  color  and  rather  transparent;  in 
southern  cattle  fever  it  may  be  red ;  and  in  azoturia  it  may  be 
brown. 

Excessive  Urination. — The  horse  is  the  most  common 
sufferer  from  excessive  secretion  of  urine.  The  most  common 
causes  are  musty  feeds,  such  as  hay,  grain  and  shipped  feeds. 
ITew  oats,  succulent  feeds  and  acrid  plants  may  sometimes  cause 


60  NON-SPECIFIC  OR  GENERAL  DISEASES 

it.  In  the  fall  of  the  year,  when  the  season  is  changing  from 
warm  to  cool  weather  and  the  horse  eliminates  less  water  from 
the  body  by  way  of  the  skin,  the  kidneys  may  become  more 
active  and  the  qnantity  of  nrine  secreted  be  greatly  increased. 
This,  however,  is  a  normal  physiological  condition  and  shonld 
not  be  confused  with  this  disease. 

The  first  symptom  noted  is  the  frequent  passing  of  a  large 
quantity  of  urine.  The  animal  drinks  more  water  than  usual 
and  the  appetite  is  poor.  Dulness  and  a  weak,  emaciated  condi- 
tion are  prominent  symptoms.  Death  occurs  unless  the  cause 
of  the  disease  is  removed.  If  the  poisonous  substance  has  been 
acting  for  some  time,  it  is  difficult  to  cure  the  animal. 

This  disease  can  be  prevented  by  eliminating  spoiled  feeds 
from  the  ration  fed  to  animals  in  our  care.  Early  in  the  attack 
the  necessary  attention  to  the  ration  and  the  feeding  of  a  clean, 
nourishing  ration  is  sufficient  to  correct  the  disease.  The 
quantity  of  water  drunk  by  the  animal  should  be  limited.  Com- 
plete rest  is  indicated.  Laxatives,  stinmlants  and  tonics  should 
be  given  if  necessary. 

Nephritis. — Congestion  and  inflammation  of  the  kidneys 
commonly  occur  in  mixed  and  specific  infectious  diseases,  such 
as  septicaemia,  pyaemia  and  influenza.  The  toxic  effect  of  spoiled 
feeds,  impure  drinking  water,  and  irritating  drugs  like  can- 
tharides  and  turpentine  may  so  irritate  the  kidneys  as  to  cause 
them  to  become  inflamed.  Chilling  of  the  skin  and  nervousness 
or  extreme  fear  may  sometimes  cause  a  congestion  of  these 
organs.  Inflammation  of  the  kidneys  is  a  common  complication 
of  azoturia.  Irritation  from  parasites  should  be  included 
among  the  causes  of  this  disease. 

The  symptoms  vary  in  the  different  stages  of  the  disease. 
During  the  period  of  active  congestion  the  quantity  of  urine 
secreted  is  increased.  The  scant  secretion  of  urine,  dark  in 
color  and  thick  or  turbid,  is  suggestive  of  an  inflammation  of 
the  kidneys.     The  animal  moves  stiffly,  the  back  may  be  arched, 


DISEASES  OF  THE  URINARY  ORGAx\S  61 

urination  is  painfnl  and  the  nrine  is  passed  in  very  small 
amounts.  The  appetite  is  irregular  or  suppressed,  the  pulse 
strong  at  hrst  but  later  small  and  weak,  and  the  body  tempera- 
ture is  elevated.  On  making  a  rectal  examination  we  find  the 
bladder  empty  and  the  kidneys  enlarged  and  sensitive. 

When  the  kidneys  become  so  badly  diseased  that  they  can  no 
longer  perform  their  function  of  separating  from  the  blood  the 
nitrogenous  end-products  of  digestion,  iirjemic  poisoning  occurs. 
In  this  later  stage  of  the  disease  the  animal  staggers  about  if 
moved,  and  finally  goes  down  in  the  stall  and  is  nnable  to  get 
up.    Death  is  usually  preceded  by  convulsions  and  coma. 

The  prognosis  is  very  unfavorable,  death  occurring  in  the 
majority  of  cases.  In  azoturia  of  horses  and  in  infectious  dis- 
eases, the  inflammation  is  nearly  always  acute.  The  color  of  the 
urine,  its  high  specific  gravity  and  the  small  quantity  passed 
are  valuable  symptoms  to  consider  in  the  recognition  of  this 
disease.  Chronic  inflammation  generally  develops  slowly  and 
may  not  give  rise  to  any  very  prominent  symptoms  at  first. 

The  preventive  treatment  of  nephritis  consists  in  careful 
nursing  of  animals  affected  with  acute  infectious  diseases,  a 
clean  water  supply  and  avoiding  the  feeding  of  spoiled  feeds. 
The  curative  treatment  is  largely  careful  nursing.  The  ani- 
mal should  be  given  comfortable,  well-ventilated  quarters  and 
complete  rest.  Chilling  of  the  skin  should  be  especially  giuirded 
against  by  protecting  the  body  with  heavy  blankets  and  apply- 
ing roller  bandages  to  the  limbs  when  necessary.  The  diet 
must  be  of  such  a  nature  as  not  to  increase  the  work  of  the 
kidneys.  For  the  first  few  days  the  animal  should  receive  very 
little  feed  or  water.  Later  a  sloppy  diet  of  sweet  milk,  green 
feed  and  mashes  should  be  fed.  Such  purgatives  as  aloes  and 
Glauber's  salts  are  indicated  at  a  very  early  stage  in  the  dis- 
ease. We  must  encourage  the  elimination  of  waste  products 
by  way  of  the  skin  in  the  larger  animals  by  vigorous  rubbing, 
blanketing  and  the  administration  of  such  drugs  as  pilocarpine. 


62  NON-SPECIFIC  OR  GENERAL  DISEASES 

If  the  animal  becomes  weak,  general  and  heart  tonics  may  be 
given. 

Cystitis. — Inflammation  of  the  bladder  is  not  an  uncommon 
disease  of  horses.  It  is  commonly  caused  by  retention  of  the 
urine,  calculi  in  the  bladder  and  chilling  of  the  body.  Irritat- 
ing druffs  that  are  eliminated  from  the  bodv  in  the  urine,  and 
infection  of  the  bladder  by  germs  may  cause  it. 

The  symptoms  are  usually  marked.  The  inflammation  is 
characterized  by  more  or  less  pain,  depending  on  the  degree 
of  the  inflammation,  and  frequent  passing  of  urine.  Only  a 
small  amount  of  urine  is  passed  at  each  attempt,  and  in  severe 
inflammation  it  may  contain  pus  or  blood.  Colicky  pains  some- 
times occur.  The  pain  is  usually  manifested  by  a  stiff,  strad- 
dling gait  and  tenderness  when  pressure  on  the  bladder  is  made 
by  introducing  the  hand  into  the  rectum  or  vagina,  and  pressing 
over  the  region  of  the  bladder.  General  symptoms,  such  as 
elevation  in  body  temperature  and  irregular  appetite,  may  be 
manifested. 

The  treatment  should  be  first  directed  at  removing  the  cause. 
If  a  cystic  calculus  is  present  in  the  bladder  it  should  be  re- 
moved. If  the  retention  of  the  urine  is  caused  by  some  local 
condition,  and  this  is  very  often  the  case  in  nervous,  well-bred 
animals,  tliis  must  first  be  corrected.  It  is  best  to  feed  green 
and  soft  feeds,  such  as  bran  mash  and  chopped  hay,  and,  if  the 
animal  will  take  them,  gruels.  A  physic  of  castor  or  linseed 
oil  should  be  given  occasionally.  It  is  very  necessary  that  the 
animal  be  kept  quiet.  Comfortable,  clean  quarters  and  a  good 
bed  should  be  provided.  Whenever  necessary  the  animal  should 
be  blanketed.  The  medicinal  treatment  consists  in  irrigating 
the  bladder  with  antiseptic  solutions,  and  administering  drugs 
that  when  eliminated  by  way  of  the  urine  may  change  its  com- 
position and  render  it  less  irritating.  The  following  mix;ture 
may  be  given:  potassium  chlorate  two  ounces,  salol  one-half 
ounce,   and  powdered  nux  vomica  one  ounce.      This  mixture 


DISEASES  OF  THE  URINARY  ORGANS  63 

may  be  divided  into  sixteen  powders.      One  of  the  powders 
should  be  given  with  each  feed. 

Retention  of  the  Urine. — This  may  be  due  to  a  variety  of 
causes.  In  the  ox  and  ram,  small  calculi  collect  in  the  vS-shaped 
curvature  of  the  urethra,  or  at  its  terminal  extremity.  In  the 
horse,  cystic  calculi  are  more  common  than  urethral.  In  cattle 
and  hogs,  fatty  secretions  from  the  inflamed  lining  membrane  of 
the  sheath  of  the  male  may  accumulate,  and  obstruct  the  flow 
of  urine  from  the  anterior  opening.  The  giving  of  feed  rich  in 
salts,  concentrated  urine  resulting  from  feeding  of  too  dry  a 
ration,  insufiiicient  exercise  and  inflammation  of  the  bladder 
are  the  direct  causes  of  calculi. 

Compression  of  the  urethra  by  growths  or  tumors,  strictures 
of  the  urethra,  distended  bladder,  spasm  of  the  neck  of  the 
bladder  in  nervous  animals,  paralysis  of  the  bladder  and  in- 
juries to  the  penis  are  common  causes  of  retention  of  the  urine. 

The  early  symptoms  in  rumhiants  are  not  usually  recognized 
until  a  day  or  two  after  retention  of  the  urine  has  occurred. 
The  symptoms  are  then  quite  marked.  The  animal  acts  dull, 
refuses  to  eat,  rumination  is  stopped,  and  there  is  a  constant 
effort  to  urinate,  as  indicated  by  the  raising  of  the  tail  and 
rhythmical  contractions  of  the  urinary  muscles  just  below  the 
anus.  Urine  may  dribble  from  the  sheath  or  the  flow  may  be 
completely  suppressed.    The  odor  of  urine  may  be  marked. 

Horses  show  symptoms  of  abdominal  pain.  The  animal 
may  move  about  the  stall,  lie  down  and  get  up  again,  or  make 
unsuccessful  attempts  to  urinate.  On  examination  the  bladder 
is  found  to  be  greatly  distended  with  urine.  In  the  horse  the 
retention  is  recognized  at  an  earlier  period  than  in  ruminants, 
because  of  the  prompt,  decided  symptom  of  pain. 

Eetention  of  the  urine  commonly  terminates  in  rupture  of 
the  bladder  in  ruminants.  When  this  occurs,  the  symptoms  of 
pain  are  less  evident.     Death  occurs  from  urajmic  poisoning 


64  NON-SPECIFIC  OR  GENERAL  DISEASES 

and  peritonitis.  The  outcome  is  less  favorable  in  ruminants 
than  in  solipeds. 

Inflammation  of  the  sheath  can  be  readily  recognized  because 
of  the  local  swelling. 

The  following  lines  of  treatment  are  recommended:  A 
ration  or  feed  that  favors  the  fonnation  of  calculi  should  not 
be  fed  to  animals;  inflammation  of  the  sheath  should  receive 
prompt  treatment — this  consists  in  irrigating  the  part  with 
warm,  soapy  or  alkaline  water,  followed  by  an  antiseptic  wash ; 
we  may  attempt  to  work  the  urethral  calculi  forward  and 
out  of  the  S-curve  in  the  urethra ;  if  this  is  unsuccessful,  ure- 
throtomy for  their  removal  may  be  attempted. 

The  retention  of  tlie  urine  in  horses,  because  of  spasm  or 
paralysis  of  certain  muscles,  may  be  treated  by  passing  the 
catheter.  Sometimes  spreading  litter  under  the  horse  and  keep- 
ing it  quiet  may  induce  it  to  urinate.  Hot  packs  over  the  region 
of  the  back  may  be  used.  The  treatment  for  calculi  is  entirely 
surgical.  The  operation  for  the  removal  of  cystic  calculi  in  the 
horse,  although  difficult,  is  followed  by  good  results. 

QUESTIONS 

1.  Describe   the   urinary   apparatus. 

2.  Give  tlie  composition  of  the  urine  and  quantity  secreted  in  the  different 

animals. 

3.  State  method  of  determining  quantity  and  composition  of  urine  secreted 

by   different   domestic   animals. 

4.  Give   tlie   causes  and  treatment   of  excessive   urination. 

5.  Give  the  causes  and  treatment  of  congestion  and  inllammation  of  the 

kidney's. 
G.  Give  the  causes  of  cystitis;  symptoms;  treatment. 
7.  Give  the  causes  and  treatment  of  retention  of  the  urine. 


CHAPTER  VII 
DISEASES  OF  THE  GENERATIVE  ORGANS 

General  Discussion. — The  study  of  the  organs  concerned 
with  the  reproduction  of  the  species  is  essential  in  order  to 
acquire  a  knowledge  of  their  several  functions.  It  is  only 
through  an  understanding  of  these  functions  that  we  can  pre- 
pare ourselves  to  correctly  recognize,  and  successfully  treat,  or 
prevent,  such  diseases  as  may  involve  the  organs  of  generation. 
A  knowledge  of  the  structure  and  function  of  the  generative 
organs  of  the  female  is  of  greater  importance  from  the  stand- 
point of  disease,  than  is  a  similar  knowledge  of  the  generative 
organs  of  the  male.  The  female  is  concerned  with  the  complete 
reproductive  process,  which  may  be  divided  into  four  stages. 
These  are  copulation,  fecundation,  gestation  and  parturition. 
The  male  is  concerned  only  with  copulation  and  fertilization  of 
the  ovum  by  the  spermatozoa,  while  the  female  must  protect 
and  nourish  the  embryo  and  foetus  until  it  has  become  suiR- 
ciently  developed  to  live  independently  of  the  protection  and 
nourishment  aiforded  it  within  the  womb.  When  the  final  stage 
of  gestation  is  reached,  birth  or  the  act  of  parturition  occurs. 

Genital  Organs  of  the  Female. — The  female  generative 
organs  are  the  ovaries,  fallopian  tubules,  uterus,  vagina,  vulva 
and  mammary  glands. 

The  ovaries  are  analogous  to  the  testicles  of  the  male. 
Their  function  is  to  secrete  ova.  This  pair  of  glands  is  sus- 
pended from  the  superior  region  (sublumbar)  of  the  abdominal 
cavity  by  folds  of  the  lining  membrane.  Leading  from  the 
ovaries,  but  connected  with  the  surface  of  these  glands  only 
during  the  period  of  oestrum  or  heat,  are  the  fallopian  tubules. 
Their  function  is  to  carry  the  ovum  from  the  ovaries  to  the 
uterus. 

5  65 


66  NON-SPECIFIC  OR  GENERAL  DISEASES 

Tlie  uterus  or  icomh  is  a  membranous  sack  situated  in  the 
sublumbar  region  and  at  the  inlet  to  the  pelvic  cavity.  It  is 
held  in  position  bv  numerous  folds  of  the  lining-  membrane  of 
the  abdominal  cavity.  We  may  divide  the  womb  into  three 
divisions,  cornua,  body  and  cervix. 

The  cornua  or  horns  are  long  and  cylindrical  in  shape. 
This  portion  of  the  womb  is  greatly  developed  in  animals,  like 
the  sow  and  bitch,  that  give  birth  to  several  young.  In  the 
impregnated  animal  the  wall  of  the  cornua  that  contains  one  or 
several  fcrtuses,  and  the  body  as  well,  becomes  greatly  tliickened 
and  the  lining  membrane  more  vascular. 

The  body  is  short  in  all  domestic  animals  and  connects  the 
horns  with  the  cervix  or  neck.  The  latter  is  represented  by  a 
narrow  portion  that  projects  backward  into  the  vagina.  In  the 
cow  the  cervix  is  less  prominent  than  in  the  mare  and  the 
tissue  that  forms  it,  quite  firm.  In  the  cow  the  opening  in  the 
cervix,  the  os,  is  very  small. 

The  vagina  is  a  musculo-membranous  canal  that  leads  from 
the  womb.  In  the  mare  and  cow  it  is  about  one  foot  in  length. 
Its  function  is  to  take  part  in  copulation  and  parturition. 

The  vulva  is  the  external  opening  of  the  maternal  passages. 
It  shows  a  vertical  slit  enclosed  by  lips,  and  interiorly  it  forms 
a  passage  that  is  continuous  with  the  vagina.  This  passage  is 
about  six  inches  long  in  the  larger  animals.  The  diiferent 
features  that  should  l)e  noted  are  the  clitoris,  a  small  erectile 
organ  located  at  the  inferior  portion  of  the  opening,  the  meatus 
urinaris,  the  external  opening  of  the  urethra,  situated  in  a  de- 
pression in  the  floor  of  the  vulva,  and  the  hymen,  an  incomplete 
membranous  partition  that  may  be  found  separating  the  vulva 
from  the  vagina. 

T'he  mammarij  (jlands  or  udders  secrete  the  milk  that 
nourishes  the  young.  The  glands  vary  in  number.  The  mare 
lias  two,  the  cow  four  (Fig.  17),  the  ewe  two  and  animals  that 
give  birth  to  several  young,  eight  or  more.     Each  gland  is  sur- 


DISEASES  OF  THE  GENERATIVE  ORGANS 


6: 


mounted  h\  a  teat  or  nipple.  The  glandular  tissue  consists  of 
ciecal  vesicles  that  form  grape-like  clusters  around  the  milk 
tuhules.  The  milk  tubules  from  the  different  portions  of  the 
gland  converge  and  form  larger  tubules  that  flnallj  empty  into 
small  sinuses  or  reservoirs  at  the  base  of  the  teat.  Leading 
from  these  sinuses  are  one  or  several  milk  ducts  that  open  at  the 
summit  of  the  teat. 

Genital  Organs  of  the  Male. — The  genital  organs  of  the 
male  are  the  testicles,   the  ducts  or  canals  leading  from  the 


I 


Fia.   17. — Photograph  of  model  of  udder  of  cow:  (A)  milk  duct;  (B)  milk  sinuses;  and  (C) 

glandular  tissue. 


testicles,  the  seminal  vesicles,  the  glands  lying  along  the  urethra, 
and  the  penis. 

The  testicles  are  the  glandular  organs  that  secrete  the 
spermatozoa,  the  essential  elements  of  the  seminal  fluid.  These 
glands  are  lodged  in  the  scrotal  sack,  situated  between  the  two 
thighs. 

Lying  along  the  superior  border  of  the  testicle  is  a  n:Tss  of 
ducts,  the  epididymis.  The  vas  deferens  is  the  canal  or  duet 
that  passes  from  the  epididymis  to  the  region  of  the  bladder  and 


68  NON-SPECIFIC  OR  GENERAL  DISEASES 

terminates  near  its  neck  by  emptying  into  the  seminal  vesicles. 

The  seminal  vesicles  are  two  membranous  pouches  situated 
just  al)ove  the  bladder.  They  act  as  receptacles  for  the  seminal 
lluid.  Two  short  ducts,  the  ejaculatory,  carry  the  seminal  fluid 
from  the  seminal  vesicles  to  the  urethra. 

The  j)rostate  gland  is  situated  near  the  origin  of  the 
urethra.  Cowper's  (jlands  lie  along  the  course  of  the  urethra 
and  n(>ar  the  origin  of  the  penis.  These  glands  empty  their 
secretions  into  the  uretln-a  and  dilute  the  seminal  fluid. 

The  penis  is  the  male  organ  of  copulation.  It  originates 
at  the  arch  of  the  ischium  and  extends  forward  between  the 
thighs.  It  may  be  divided  into  fixed  and  free  portions.  The 
free  portion  is  lodged  in  the  prepuce  or  sheath,  but  at  the  time 
of  erection  protrudes  from  it. 

Sterility,  Impotency. — Fecundation  does  not  always  follow 
intercourse  of  the  male  and  female.  Im})otency  in  the  male  and 
sterility  in  the  female  frequently  occur. 

The  causes  are  quite  varied.  A  nonnal  copulation  may  be 
impossible  because  of  injuries  to,  and  deformities  of  the  parts 
and  tumor  growths.  Deformed  genital  organs  and  obstructions 
of  the  OS  by  growths  and  scar  tissue  are  causes  of  sterility  in 
the  female. 

Failure  to  breed  is  commonly  caused  by  faulty  methods  of 
feeding  and  care.  Over-feeding  and  insutHcient  exercise  may 
result  in  the  body  tissues  becoming  loaded  with  fat.  This  may 
cause  a  temporary  sterility,  but  if  persisted  in,  as  is  frequently 
the  case  in  show  animals,  the  sterility  becomes  jDcrmanent  be- 
cause of  the  genital  glands  failing  to  secrete  ova  and  spermatozoa, 
or  the  lack  of  vitality  of  the  male  and  female  elements.  Old 
age  and  debility  from  disease  or  poor  care  may  induce  loss  of 
sexual  desire  and  an  absence  of,  or  weakened  spermatozoa  in  the 
seminal  fluid.  The  refusal  of  the  male  to  serve  certain  females 
is  sometimes  noted. 

Tuberculosis  may  affect  the  ovaries  and  cause  permanent 


DISEASES  OF  THE  GENERATIVE  ORGANS  69 

sterility.  In  inflammation  of  the  lininj^  membrane  of  the  womb 
and  vagina,  the  secretions  are  abnormal  and  may  collect  in  the 
womb  and  the  passages  leading  to  it.  These  secretions  destroy 
the  vitality  of  the  spermatozoa,  and  this  condition  may  be  con- 
sidered a  common  cause  of  sterility  in  the  larger  animals.  Many 
vigorous  young  males  are  made  impotent  by  excessive  copulation. 
The  excessive  use  of  the  male  at  any  time  may  result  in  failure 
to  impregnate  a  larg-e  percentage  of  the  females  that  he  serves. 

Barren  females  do  not  become  pregnant  after  frequent  inter- 
course with  the  male.  Young  sterile  females  may  not  come  in 
heat.  Sometimes  unnatural  periods  of  heat  are  manifested,  the 
animal  coming  in  heat  frequently  or  remaining  in  heat  for  a 
longer  period  than  usual.  This  sometimes  occurs  in  tuberculo- 
sis of  the  ovaries.  In  chronic  inflammation  of  the  maternal 
passage  there  is  more  or  less  discharge  from  the  vulva.  Both 
sexes  may  be  overly  fat  or  weakened  and  debilitated  by  disease. 
Deformity  of  the  generative  organs  and  growths  may  be  found 
on  making  an  examination.  Absence  of,  or  lack  of  vitality  of 
the  spermatozoa  may  be  determined  by  microscopic  examination 
of  the  seminal  fluid. 

The  treatment  is  largely  preventive.  It  is  very  important 
that  breeding  animals  be  kept  in  proper  physical  condition  by 
avoiding  the  feeding  of  too  heavy  or  too  light  a  ration,  and 
allowing  them  sufficient  exercise.  The  male  is  more  often 
affected  by  the  latter  cause  than  the  female.  Young  males 
should  not  be  given  excessive  intercourse  with  the  female.  The 
excessive  use  of  the  stallion  can  be  avoided  by  practising  arti- 
ficial impregnation  of  a  part  of  the  mares  that  he  is  called  to 
serve.  vSterility  caused  by  growths  and  closure  of  the  os  may 
be  corrected  by  an  operation. 

Before  practicing  a  course  of  treatment  for  the  relief  of 
sterility  in  either  male  or  female,  its  advisability  and  the  line 
of  treatment  should  first  be  determined  by  a  careful  examination 
of  the  parts.  This  examination  should  be  made  by  a  veterinarian. 
A  large  percentage  of  the  cases  of  sterility  are  due  to  diseased 
ovaries   and  inflammation   of  the  uterine  mucous  membrane. 


70  NON  SPECIFIC  OR  GENERAL  DISEASES 

Direct  treatment  to  tlie  diseased  parts  should  be  practiced,  as 
irrigating  the  maternal  passage  leading  to  the  womb  is  of  no 
use.  The  treatment  usually  practiced  is  manipulation  of  the 
ovaries  by  introducing  the  hand  into  the  rectum  and  pressing 
on  them  through  its  wall  and  retracting  the  uterus,  dilating  the 
OS  and  irrigating  the  lOrgan  with  a  disinfecting  solution. 

Fat  animals  should  be  subject  to  a  rigid  diet  and  given 
plenty  of  exercise.  In  treating  weak  or  debilitated  animals  the 
cause  should  lirst  be  removed.  A  heavy  grain  ration  should  be 
fed  for  the  purpose  of  stimulating  the  sexual  desire  in  the 
cases  mentioned. 

Signs  of  Pregnancy. — The  signs  which  characterize  preg- 
nancy are  numerous  and  varied.  For  convenience  we  may 
classify  the  many  signs  of  pregnancy  under  two  heads,  probable 
and  positive.  Under  the  head  of  probable  signs,  we  may  group 
tiie  following  symptoms  of  pregnancy:  cessation  of  heat; 
changes  in  the  animal's  disposition;  increase  in  the  volume  of 
the  abdomen  and  tendency  to  put  on  fat.  The  positive  signs 
are  the  change  in  the  volume  of  the  udder;  the  secretion  of 
milk  ;  the  movement  of  the  foetus  and  presence  of  the  foetus  in 
the  womb,  as  determined  by  rectal  examination  or  by  the  feel 
of  the  al)domen. 

The  probable  signs  are  not  reliable,  and  should  be  considered 
only  in  connection  with  some  positive  sign.  Persons  who  base 
their  opinion  of  the  condition  of  an  animal  that  is  supposed  to 
be  pregiumt  on  probable  signs,  are  frequently  mistaken.  It  has 
frequently  ha])pened  that  animals  whose  condition  was  not  at  all 
certain  have  given  ])irth  to  young,  without  giving  rise  to  what 
may  be  termed  characteristic  probable;  signs. 

The  earliest  probable  symptom  is  the  cessation  of  heat.  In 
the  large  pregnant  animals,  irregnlar  heat  periods  may  occur, 
but  in  the  majority  of  cases  we  may  safely  consider  the  animal 
impregnated  if  several  heat  periods  are  passed  over. 

It  has  been  generally  observed  that  the  disposition  of  the 
pregnant  animal  is  changed.     They  become  more  quiet  and  less 


DISEASES  OF  THE  GENERATIVE  ORGANS  71 

nen'ous  and  irritable.  The  tendency  of  pregnant  animals  to  put 
on  fat  is  frequently  taken  advantage  of  by  the  stockman,  who 
may  allow  the  boar  to  run  with  the  herd  during  the  latter  period 
of  fattening. 

The  increase  in  the  volume  of  the  al)domen  may  be  con- 
sidered a  jmsitive  sign  of  pregnancy  in  the  small  animals,  but 
in  the  mare  and  cow  it  can  not  be  depended  on.  Animals  that 
are  pregnant  for  the  first  time,  do  not  show  as  great  an  increase 
in  the  volume  of  the  abdomen  as  do  animals  that  have  gone 
through  successive  pregnant  periods.  The  volume  of  the  abdo- 
men may  vary  greatly  in  the  different  individuals,  and  can  not 
be  depended  on  as  a  positive  indication  of  pregnancy  during 
the  first  two-thirds  of  the  period  of  pregnancy  in  the  larger 
domestic  animals. 

Comparatively  early  in  pregnancy,  the  presence  of  a  fretus 
can  be  determined  hx  feeling  the  uterus  through  the  wall  of  the 
rectum.  In  the  small  domestic  animals  the  feeling  of  the  abdo- 
men gives  the  best  results.  In  the  cow  this  method  of  diag- 
nosis is  practised  during  the  latter  periods  of  pregnancy.  The 
examiner  stands  with  his  back  toward  the  animal's  head,  and  on 
the  right  side  of  the  cow  and  the  left  side  of  the  mare.  The 
palm  of  the  hand  is  applied  against  the  abdominal  wall,  about 
eight  or  ten  inches  in  front  of  the  stifle  and  just  below  the  flank. 
Moderate  pressure  is  used,  and  if  a  hard,  voluminous  mass  is 
felt,  or  if  the  fcetus  moves,  it  is  a  sure  sign  that  the  animal  is 
pregnant.  It  is  not  uncommon  for  the  foetus  to  show  some 
movement  in  the  morning,  or  after  the  animal  drinks  freely  of 
cold  water.  The  increase  in  the  volume  of  the  udder  occurs 
at  a  comparatively  early  period  in  animals  that  are  pregnant 
for  the  flrst  time.  The  secretion  of  milk  and  the  dropping  of 
the  muscles  of  the  quarters  indicate  that  parturition  is  near. 
The  Abderhalden  test  for  determining  whether  or  not  an  animal 
is  pregnant  is  now  practised. 

Hygiene  of  Pregnant  Animals. — Pregnant  animals  that  are 


72  NON-SPECIFIC  OR  GENERAL  DISEASES 

confined  in  a  jiasture  that  is  free  from  injurious  weeds  and  not 
too  rough  or  hilly,  and  where  the  animals  have  access  to  clean 
water  and  the  necessary  shelter,  seldom  suffer  from  an  abnormal 
birth.  Here  they  live  under  the  most  favorable  conditions  for 
taking  exercise,  securing  a  suitable  diet  and  avoiding  injury. 
It  may  not  be  possible  in  managing  breeding  animals  to  provide 
such  surroundings  at  all  times,  but  we  should  observe  every 
possible  hygienic  precaution,  especially  if  the  animal  has  reached 
the  later  periods  of  pregnancy. 

All  pregnant  animals  are  inclined  to  be  lazy,  but,  if  permitted, 
will  take  tlie  necessary  exercise.  Pregnant  mares  are  usually 
worked.  Such  exercise  does  no  harm,  providing  the  work  is 
not  hard  or  of  an  unusual  character.  Cows  are  usually  sub- 
ject to  more  natural  conditions  than  other  domestic  animals. 

Protecting  pregnant  animals  against  injuries  resulting  from 
crowding,  slipping  and  fighting  is  an  important  part  of  their 
care.  Injuries  from  crowding  together  in  the  sleeping  quarters 
and  about  feeding-troughs,  or  through  doors  and  climbing  over 
low  partitions  are  common  causes  of  injury  in  pregnant  sows. 
Oowding  together  in  the  stable  or  yard,  or  through  doorways, 
fighting,  and  slipping  on  floors,  or  icy  places  sometimes  results 
in  injury.  It  is  rare,  however,  for  cows  to  abort  from  an  in- 
jury, but  parturition  may  not  be  completely  free  from  dis- 
agreeable complications.  Under  the  conditions  mentioned  re- 
tention of  the  fetal  membranes  is  common. 

Ewes  frequently  suffer  from  too  close  confinement  during 
late  winter.  Sows  are  often  subject  to  the  most  unhygienic 
conditions.  This  is  shown  in  the  heavy  death-rate  in  sows 
and  pigs.  During  the  late  winter  and  early  spring  the  condi- 
tions may  be  such  as  not  to  permit  of  exercise.  Stoimy,  snowy, 
muddy  weather  is  common  at  this  season  of  the  year.  Persons 
caring  for  ewes  and  sows  should  see  that  they  take  suflicient 
exercise.  It  may  be  necessary  to  driMe  them  about  for  a  short 
time  each  dav.     At  such  times  it  may  be  advisable  to  give  them 


DISEASES  OF  THE  GENERATIVE  ORGANS  73 

a  laxative  dose  of  oil,  or  give  a  laxative  with  the  feed.  When 
there  is  any  indication  of  constipation,  this  should  be  practised. 
Pregnant  animals  should  be  fed  carefully.  We  may  feed 
animals  that  are  not  in  this  condition  in  a  careless  fashion,  but 
if  pregnant,  over-feeding,  the  feeding  of  a  fattening  ration,  or 
spoiled  feed,  and  sudden  changes  in  the  feed  can  not  be  practised 
with  any  degree  of  safety.  A  bulky  ration  of  dry  feed  and 
drinking  impure,  or  too  little,  water  may  cause  constipation, 
acute  indigestion  and  abortion.  The  ration  fed  should  contain 
the  necessary  inorganic  and  organic  elements  for  the  building 
up  of  the  body  tissues  of  the  foetus. 

At  the  end  of  the  parturition  period,  separate  quarters  should 
be  provided.  The  mare  or  cow  should  be  given  a  comfortable 
clean  stall  away  from  the  other  animals.  The  ewe  should  be 
provided  wath  a  warm  room  if  the  weather  is  cold.  It  is  always 
best  to  give  the  sow  a  separate  pen  that  is  dry  and  clean,  and 
away  from  the  other  animals.  All  danger  from  injury  to  the 
mother  and  young  should  be  guarded  against. 

Abortion.~The  expulsion  of  the  foetus  at  any  time  during 
the  period  of  gestation,  when  it  is  not  sufficiently  developed  to 
live  independently  of  the  mother,  is  termed  abortion.  Abortion 
may  be  either  accidental  or  infectious.  Accidental  abortion  is 
more  commonly  met  with  in  the  mare  and  sow  than  the  in- 
fectious form.     In  ruminants  the  opposite  holds  true. 

The  causes  of  accidental  almrtion  are  faulty  methods  of 
feeding  and  care.  Injuries,  acute  indigestion,  mouldy,  spoiled 
feeds,  chilling  resulting  from  exposure  and  drinking  ice-cold 
water,  nervousness  brought  on  by  fright,  or  excitement  and 
general  diseases  are  the  common  causes  of  abortion. 

Infectious  abortion  is  most  common  in  cows.  Other  domes- 
tic animals  that  may  be  affected  are  the  mare,  sow  and  ewe. 

It  is  caused  by  a  specific  genu.  The  Bacillus  ahortu.s  of 
Bang  is  the  cause  of  abortion  in  cows,  but  the  specific  germ  that 
produces  abortion  in  other  species  of  animals  has  not  been  proven. 


74  NON-SPECIFIC  OR  GENERAL  DISEASES 

In  this  country,  Keer,  Good,  Giltner  and  others  have  proven 
that  the  Bang  hacillus  of  abortion  is  infectious  for  other  species 
of  animals,  and  outbreaks  of  this  disease  have  been  said  to  occur 
among  breeding  ewes  pastured  and  fed  on  infected  premises. 
Its  infectiousness  for  the  females  of  otlier  species  has  never 
been  proven  in  natural  outbreaks. 

The  disease-producing  germs  are  present  in  the  body  of  the 
foetus,  the  fetal  membranes,  the  discharge  from  the  maternal 
passages,  the  ficces  and  milk  of  aborting  animals.  The  male 
may  carry  tlie  infection  in  the  sheath,  urethra  and  on  the  penis. 
The  natural  avenues  of  infection  are  the  maternal  passages  and 
digestive  tract. 

It  is  very  seldom  that  abortion  is  carried  from  one  herd 
to  another  by  means  other  than  through  the  breeding  of  ani- 
mals free  from  abortion  to  animals  affected  by  this  disease. 
The  purchase  of  a  hull  or  coiv  from  an  infected  herd  and  breed- 
ing them  to  animals  that  are  free  from  disease,  is  a  common 
method  of  spreading  the  disease.  After  serving  the  diseased 
animal,  the  male  may  carry  the  bacillus  of  abortion  into  the 
maternal  passages  of  the  next  cow  he  serves.  There  are  numer- 
ous cases  on  record  where  the  bull  was  a  permanent  carrier  of 
the  Bacillus  ahorlus  and  infected  nearly  every  anifnal  served. 
The  distribution  of  the  disease  in  the  herd  following  the  intro- 
duction of  a  cow,  sow,  or  ewe  that  has  aborted  before  or  after 
being  purchased,  takes  place  through  contact  of  the  other  ani- 
mals with  the  virus  that  may  be  present  on  the  floor,  or  in  the 
manure,  or  by  taking  the  virus  into  the  digestive  tract  along 
with  the  feed  and  drinking  water.  Experimental  evidence  indi- 
cates the  latter  avenue  of  infection. 

The  stallion  is  the  most  common  source  of  infectious  abor- 
tion in  mares.  An  infected  stallion  may  distribute  the  disease 
to  a  large  percentage  of  the  mares  that  he  serves.  For  this 
reason  nearly  all  of  the  marcs  in  a  certain  localit^y  may  abort. 

In  case  the  infection  occurs  at  the  time  of  service,  the  abor- 


DISEASES  OF  THE  GENERATIVE  ORGANS  75 

tioii  usually  takes  place  during-  the  lirst  ball"  of  the  period  of 
pregnancy.  Cows  that  become  pregnant  without  recovering 
from  the  inflannnation  of  the  lining  membrane  of  the  genital 
tract,  may  abort  at  a  very  early  period.  McFadyean  and  vStock- 
man  from  the  artificially  inoculated  cases  of  infectious  abortion 
in  cows,  showed  that  the  period  of  incubation  averaged  12G  days. 

The  symptoms  of  accidental  abortion  are  extremely  variable. 
Animals  that  abort  during  the  early  periods  of  pregnancy  may 
show  so  little  disturbance,  that  the  animal  can  be  treated  as  if 
nothing  had  happened.  During  the  latter  half  of  pregnancy, 
and  especially  w^hen  the  accident  is  caused  by  an  injury,  the 
s^TQptoms  are  more  serious.  Loss  of  appetite,  dulness,  restless- 
ness, abdominal  pain  and  hemorrhage  are  the  symptoms  com- 
monly noted.  If  the  foetus  is  dead,  it  may  be  necessary  to 
assist  tbe  animal  in  expelling  it.  In  the  latter  case,  death  of  the 
mother  may  occur. 

A  slight  falling  of  the  flanks,  swelling  of  the  lips  of  the 
vulva  and  a  retention  of  the  fetal  membranes,  or  discharge  from 
the  vulva  may  be  the  only  symptoms  noted  at  the  time  abortion 
occurs. 

The  symptoms  of  infectious  ahortion  vary  in  the  different 
periods  of  preg-nancy.  At  an  early  period,  the  foetus  may  be 
passed  with  so  little  evidence  of  labor  that  the  animal  pays 
little  attention  to  it.  The  recurrence  of  heat  may  be  the  first 
intimation  of  the  abortion.  All  cases  of  abortion  are  followed  by 
more  or  less  discharge  from  the  vulva.  This  is  especially  true 
if  the  fetal  membranes  are  retained.  In  such  cases,  the  dis- 
charge has  a  very  disagTeeable  odor.  In  most  cases  the  foetus 
is  dead.  When  born  alive,  it  is  weak  and  puny,  and  usually 
dies  or  is  destroyed  within  a  few  days.  When  the  attendant 
fails  to  give  the  animal  the  necessary  attention,  or  is  careless 
in  his  manipulation  of  the  parts,  inflammation  of  the  womb, 
caused  by  the  decomposition  of  the  retained  membranes,  or  the 
introduction  of  irritating  germs  on  the  ropes,  instruments  and 


76  NON-SPECIFIC  OR  GENERAL  DISEASES 

hands,  may  occur.     Death  commonly  follows  this  complication. 

It  is  very  important  that  the  infectious  form  be  diagnosed 
early  in  the  outbreak.  For  all  practical  purposes  we  are  justi- 
fied in  diagnosing  infectious  abortion,  if  several  animals  in  the 
herd  abort,  especially  if  it  follows  tlie  introduction  of  new  ani- 
mals. ]\[ethods  of  serum  diagnosis,  the  agglutination  and  com- 
plement-fixation tests,  are  now  used  in  the  diagnosis  of  this 
disease. 

The  preventive  treatmeni  of  the  accidental  form  consists  in 
avoiding  conditions  that  may  result  in  this  accident.  Pregnant 
animals  should  not  be  exposed  to  injuries  from  other  animals 
or  from  the  surroundings.  Animals  which  show  a  predisposition 
to  abort  should  not  be  bred.  We  should  see  that  all  animals  re- 
ceive the  necessary  exercise  and  a  proper  ration. 

If  the  animal  indicates  by  her  actions  that  abortion  may  take 
place,  we  should  give  her  comfortable,  quiet  quarters.  It  is 
very  necessary  to  keep  her  quiet,  and  if  restless,  morphine  may 
be  given.  A  very  light  diet  should  be  fed  and  constipation  pre- 
vented by  administering  a  laxative.  The  necessary  attention 
should  be  given  in  case  abortion  occurs. 

The  enforcement  of  preventive  or  quarantine  measures  is 
very  important  in  the  control  of  infectious  abortion.  This  is 
especially  true  of  breeding  herds  and  dairy  cows.  Breeders 
do  not  recognize  the  importance  of  keeping  their  herds  clean 
or  free  from  disease.  It  is  a  well-known  fact  among  stockmen 
tluit  al)()rtion  and  other  infectious  diseases  have  been  frequently 
introduced  into  the  herd  through  the  purchase  of  one  or  more 
breeding  animals.  Because  of  the  prevalence  of  infectious  abor- 
tion among  cows,  it  is  advisable  to  subject  newly  purchased 
breeding  animals,  or  a  cow  that  has  been  bred  outside  of  the 
herd,  to  a  short  (piarantine  period  before  allowing  them  to  mix 
with  the  herd.  'Hie  breeding  of  cows  from  neighboring  herds  to 
the  herd  bull  is  not  a  safe  practice.  In  communities  where  there 
are  outbreaks  of  this  disease,  animals  that  abort,  or  show  indi- 


DISEASES  OF  THE  GENERATIVE  ORGANS  77 

cations  of  aborting,  should  be  qnarantined  for  a  period  of  from 
two  to  three  months.  The  separation  from  the  herd  should  be  so 
complete  as  to  eliminate  any  danger  of  carrying  the  disease  to 
the  healthy  animals  on  the  clothing  and  farm  tools.  If  this 
method  of  control  were  practised  at  the  very  beginning  of  the 
outbreaks,  the  disease  could  be  checked  in  the  large  majority  of 
herds. 

The  f(rtus  and  membranes  should  be  destroyed  by  burning. 
In  case  the  aninuil  does  not  pass  the  fetal  membranes,  they 
should  l)e  completely  removed.     In  the  cow,  it  is  advisable  to 
wait  twenty-four  hours  before  doing  this.     The  ai^imal's  stall 
should  be  thoroughly  cleaned  and  disinfected.     It  is  very  ad- 
visable to  give  the  entire  stable  a  thorough  disinfecting.     For 
this  purpose  a  three  or  four  per  cent  water  solution  of  liquor 
cresolis  compound  may  be  used.     It  is  advisable  to  apply  it 
with  a  spray  pump.      The  floor  and  feed  troughs  should  be 
sprinkled  daily  with  the  disinfectant.     All  manure  should  be 
removed  to  a  place  where  the  animals  can  not  come  in  contact 
with  it.     It  is  not  advisable  to  confine  the  cows  to  a  small  yard. 
The  more  range  they  have  the  easier  it  is  to  control  the  disease. 
Individual  treatment  is  very  necessary.     In  infectious  abor- 
tion the  mucous  lining  of  the  womb  and  the  passages  leading 
to  it  become  inflamed.     This  should  be  treated  by  irrigating  the 
parts  with  a  warm  water  solution  of  a  disinfectant  that  is  non- 
irritating.     This  treatment  should  be  repeated  daily  for  a  period 
of  from  two  to  four  weeks.     We  must  be  very  careful  not  to 
irritate  the  parts.     A  one-half  per  cent  water  solution  of  liquor 
cresolis  compound  may  be  used. 

Animals  that  abort  should  not  be  bred  until  they  have  com- 
pletely recovered.  Small  animals  that  have  no  special  value  as 
breeding  animals  should  be  marketed.  Cows  and  mares  should 
not  be  bred  for  a  period  of  at  least  three  months. 

Infected  males  should  not  be  used  for  service.     The  male 


78  NON-SPECIFIC  OR  GENERAL  DISEASES 

should  receive  the  necessary  attention  in  tlie  way  of  irrigating 
the  sheath  hefore  and  after  each  service. 

Physiology  of  Parturition. — Parturition  or  birth,  when 
occurring  in  the  mare,  is  designated  as  foaling;  in  the  cow, 
calving;  in  the  sheep,  lamhing;  and  in  the  sow,  farrowing.  A 
normal  or  natural  hirth  occurs  when  no  complications  are  present 
and  the  mother  needs  no  assistance.  When  the  act  is  compli- 
cated and  prolonged,  it  is  termed  abnormal  birth.  The  length 
of  time  required  for  different  individuals  of  the  same  species 
to  give  birth  to  their  young  varies  widely.  It  may  require 
but  a  few  minutes,  or  be  prolonged  for  a  day  or  more.  The 
cause  of  this  variation  in  the  length  of  time  required  for  differ- 
ent animals  to  bring  forth  their  young,  can  be  better  understood 
if  we  study  the  anatomy  of  the  parts  and  their  functions. 

Throughout  the  pregnant  period  the  expulsion  of  the  foetus 
is  being  prepared  for.  As  the  foetus  develops  there  is  a  corre- 
sponding development  of  the  muscular  wall  of  the  womb.  The 
last  period  of  pregiiancy  is  characterized  by  the  relaxation  of  the 
muscles  and  ligaments  that  form  the  pelvic  walls,  and  a  relaxa- 
tion and  dilation  of  the  maternal  passages.  In  addition,  de- 
generative changes  occur  in  the  structures  that  attach  the  foetus 
to  the  womb,  the  normal  structures  l)eing  gradually  destroyed 
by  a  fatty  degeneration.  This  results  in  a  separation  between  the 
fetal  and  maternal  placenta.  The  contents  of  the  womb  begin 
to  affect  the  organ  in  the  same  manner  as  a  foreign  body,  irritat- 
ing the  nerve  endings  and  producing  contractions  of  the  muscles. 
These  contractions  of  the  muscles  help  greatly  in  breaking  down 
the  attach?nents  until  finally  the  labor  pains  begin  in  earnest, 
and  the  foetus  is  gradually  forced  out  of  the  womb,  through  tlie 
dilated  os  and  into  the  vagina  and  vulva. 

A  normal  birth  is  possible,  only  when  the  expelling  power 
of  the  womb  is  able  to  overcome  the  resistance  offered  by  the 
foetus  and  its  membranes^  the  pelvic  walls  and  the  vagina  and 
vulva. 


DISEASES  OF  THE  GENERATIVE  ORGANS 


79 


The  relative  size  of  the  fa'tus  to  the  inlet  of  the  pelvic 
cavity  and  its  position  are  the  most  important  factors  for  the 
veterinarian  and  stockman  to  consider  (Fio-.  18).  On  leaving 
the  womb,  the  ftctus  passes  into  the  vagina  and  vnlva.  This 
portion  of  the  maternal  passages  is  sitnated  in  the  pelvic  cavity 
which  continnes  the  abdominal  cavity  posteriorly.     The  pelvic 


Fig.  18. — Photograph  of  model  of  uterus  ol  cow  containing  a  fcEtus:  (B)  fcetus; 
(E)  umbilical  cord;  (H)  placenta;  (A,  A)  horn  containing  fcEtus;  and  (C)  opposite  horn. 
Note  the  difference  in  the  development  of  the  two  horns. 

walls  are  formed  by  bones  and  ligaments  that  are  covered  by 
heavy  muscles.  As  previously  mentioned,  the  ligaments  and 
muscles  relax  toward  the  end  of  pregnancy  in  order  to  prepare 
the  way  for  the  passage  of  the  foetus.  Before  entering  the  pelvis 
it  is  necessary  for  the  foetus  to  be  forced  through  the  inlet  to  this 
cavitv.    This  is  the  most  difficult  part  of  the  birth,  as  the  bones 


80  NON-SPECIFIC  OR  GENERAL  DISEASES 

that  form  the  framework  of  the  pelvis  completely  enclose  the 
entrance  to  it.  It  is  only  in  the  young  mother  that  the  pelvic 
bones  give  way  slightly  to  the  pressure  on  them  by  the  foetus. 
It  can  be  readily  understood,  that  when  the  young  is  large  in 
proportion  to  the  diameter  of  the  pelvic  inlet,  it  is  difficult 
for  it  to  pass  through.  This  occurs  when  mothers  belonging 
to  a  small  breed,  are  impregnated  by  a  sire  belonging  to  a  large 
breed  of  animals.  It  may  also  occur  if  tlie  mother  is  fed  too 
fattening  a  ration  and  not  permitted  sufficient  exercise. 

The  part  of  the  fcrtus  that  presents  itself  for  entrance  into 
the  pelvic  cavity  and  its  position  are  of  the  greatest  impor- 
tance in  giving  birth  to  the  young.  Either  end  of  the  foetus, 
or  its  middle  portion  may  be  presented  for  entrance.  The 
anterior  and  posterior  presentations  may  be  modified  by  the 
position  that  the  foetus  assumes.  It  may  be  in  a  position  that 
places  tlie  back  or  vertebrse  opposite  the  upper  j)ortion  of  the 
inlet,  or  the  floor  or  sides  of  the  pelvic  cavity.  These  posi- 
tions may  be  modified  by  the  position  of  one  or  both  limbs,  or  the 
head  and  neck  being  directed  forwards  instead  of  backwards. 
In  the  transverse  presentations,  the  back,  or  the  feet  and  abdo- 
men of  the  fo-tus  may  present  themselves  for  entrance  to  the 
pelvic  cavity.  These  presentations  may  show  three  j)ositions 
each.  The  head  may  be  opposite  the  upper  walls  of  the  inlet, 
the  foetus  assuming  a  dog-sitting  position,  or  it  may  lie  on  either 
side. 

In  order  to  overcome  the  friction  between  the  foetus  and  the 
wall  of  the  maternal  passages,  these  parts  are  lubricated  by  the 
fluids  that  escape  from  the  "  water  bags."  If  birth  is  prolonged 
and  the  passages  become  dry,  birth  is  retarded.  The  hair  offers 
some  resistance  in  a  posterior  presentation.  Young  mares  that 
become  hysterical  have  abnormal  labor  pains  that  seem  to  hold 
the  foetus  in  the  womb  instead  of  expelling  it. 

Care  of  the  Mother  and  Young. — Although  birth  is  gener- 
ally easy  in  the  different  domestic  animals,  it  may  be  difficult 


DISEASES  OF  THE  GENERATIVE  ORGANS  81 

aud  complicated,  and  it  is  of  the  greatest  economic  importance 
that  special  attention  be  given  the  mother  at  this  time.  It  is 
very  necessary  for  her  to  be  free  if  confined  in  a  stall.  If  run- 
ning in  a  pasture  or  lot,  the  necessary  shelter  from  storms,  cold 
or  extreme  heat  should  be  provided.  Other  farm  animals,  such 
as  hogs,  horses  and  cattle,  should  not  be  allowed  to  run  in  the 
same  lot  or  pasture. 

When  parturition  commences,  the  mother  should  be  kept 
under  close  observation.  If  the  labor  is  difficult  and  prolonged, 
we  may  then  examine  the  parts  and  detennine  the  cause  of  the 
abnormal  birth.  Unnecessary  meddling  is  not  advisable.  Be- 
fore attempting  this  examination,  the  hands  should  be  cleaned 
and  disinfected,  and  the  finger  nails  shortened  if  necessary. 
The  different  conditions  to  be  determined  are  the  nature  of  the 
labor  pains,  the  condition  of  the  maternal  passages,  and  the 
position  and  presentation  of  the  foetus.  In  the  smaller  animals 
this  examination  may  be  difficult.  In  prolonged  labor  the  parts 
may  be  found  dry  and  the  labor  pains  violent  and  irregular,  or 
weak.  The  fcrtus  may  be  jammed  tightly  into  the  pelvic  inlet, 
it  may  be  well  forward  in  the  womb,  the  head  and  fore  or  hind 
limbs  may  be  directed  backwards,  or  one  or  more  of  these  parts 
may  be  directed  forward  in  such  a  position  as  to  prevent  the 
entrance  of  the  foetus  into  the  pelvic  inlet.  Sometimes  the 
foetus  is  in  a  transverse  position.  The  parts  that  present  them- 
selves at  the  pelvic  inlet  should  be  carefully  examined  and  their 
position  determined.  The  necessary  assistance  should  then  be 
given.  Any  delay  in  assisting  in  the  birth  may  result  in  the 
death  of  the  young  or  mother,  or  both.  On  the  other  hand, 
unintelligent  meddling  may  aggravate  the  case  and  render  treat- 
ment difficult  or  impossible.  There  is  no  line  of  veterinary 
work  that  requires  the  attention  of  a  skilled  veterinarian  more 
than  assisting  an  irregiilar  or  abnormal  birth. 

The  attendant  must  guard  against  infecting  the  parts  with 
irritating  germs,  or  irritating  and  injuring  them  in  any  way. 
6 


82    .  NON-SPECIFIC  OR  GENERAL  DISEASES 

The  hands,  instniments,  and  cords  must  be  freed  from  germs 
by  "washing  with  a  disinfectant,  or  sterilization  with  heat.  The 
quarters  must  be  clean  in  order  to  prevent  contamination  of  the 
instruments  and  clothing  of  the  attendant  by  filth.  Extreme 
force  is  injurious.  For  illustration,  we  may  take  a  case  of 
difficult  birth  caused  by  an  unusually  large  fa?tus.  Both  pres- 
entation and  ])Osition  are  nonnal,  the  forefeet  and  head  having 
entered  the  pelvic  cavity,  but  the  shoulders  and  chest  are  jammed 
tightly  in  the  inlet,  and  the  progress  of  the  fcctus  along  the 
maternal  passages  is  retarded.  By  using  sufficient  force,  we 
may  succeed  in  delivering  the  young,  but  by  pulling  on  one  limb 
until  the  shoulder  has  entered  the  pelvis,  and  repeating  this 
with  the  opposite  limb  we  are  able  to  deliver  the  young  without 
exposing  the  mother  to  injury.  It  may  be  necessary  to  change 
an  abnormal  presentation,  or  position,  to  a  nonnal  presentation, 
or  as  nearly  normal  as  possible.  This  should  be  done  before 
any  attempt  is  made  to  remove  the  foetus. 

Following  birth  the  mother  should  not  be  unnecessarily  dis- 
turbed. The  quarters  should  be  clean,  well  bedded  and  venti- 
lated, but  free  from  draughts.  If  the  parturition  has  been 
normal,  a  small  quantity  of  easily  digested  feed  may  be  fed. 
If  weak  and  feverish,  feed  should  be  withheld  for  at  least  twelve 
hours.  The  mare  should  be  rested  for  a  few  weeks.  The  young 
needs  no  special  attention  if  it  is  strong  and  vigorous,  but  if 
weak,  it  may  be  necessary  to  support  it  while  nursing,  or  milk 
the  mother  and  feed  it  by  hand.  If  the  mother  is  nervous  and 
irritable,  it  may  be  necessary  to  remove  the  young  temporarily 
to  a  place  where  she  can  hear  and  see  it,  until  a  time  when  she 
can  be  induced  to  care  for  it.  The  principal  attention  required 
for  young  pigs  is  protection  against  being  crushed  by  the  mother. 
The  cutting  off  and  ligation  of  the  umbilical  cord  at  a  point  a 
few  inches  from  tlio  abdomen,  and  applying  tincture  of  iodine 
or  any  reliable  disinfectant  is  very  advisable  in  the  colt  and  calf. 

Retention  of  the  Fetal  Membranes. — The  fcptus  in  envel- 


DISEASES  OF  THE  GENERATIVE  ORGANS 


83 


oped  by  several  layers  of  membranes.  The  external  envelope,  the 
chorion,  is  exactly  adapted  to  the  lltel1^s.  The  innermost  enve- 
lope, the  amnion,  encloses  the  fietns.  Coverinii'  the  external 
face  of  the  amnion  and  lining  the  inner  face  of  the  chorion  is 
a  donble  membrane,  the  allantois.  The  envelopes  mentioned 
are  not  the  only  protection  that  the  fd'tns  has  against  injury. 
It  is  enveloped  in  fluids  as  well.     Immediately  surrounding  it  is 


Fig.  19. — Placenta  of  cow. 

the  liquor  amnii,  and  within  the  allantois  is  the  allantoic  fluid. 
The  placenta  is  a  highly  vascular  structure  spread  out  or 
scattered  over  the  surface  of  the  chorion  and  the  mucous  mem- 
brane of  the  uterus,  that  attaches  the  fcetus  and  its  envelopes  to 
the  womb  (Fig.  19).  It  is  by  means  of  this  vascular  apparatus 
that  the  fretus  is  furnished  with  nourishment.  The  fetal  and 
maternal  placentas  are  made  up  of  vascular  villi  and  depres- 
sions that  are  separated  only  by  the  thin  walls  of  capillaries, 


84  NON-SPECIFIC  OR  GENERAL  DISEASES 

and  a  layer  of  epithelial  cells.  This  pennits  a  change  of 
material  betrween  the  fetal  and  maternal  circulation.  The 
arrangement  of  the  placenta  differs  in  the  different  species.  In 
the  mare  and  sow,  the  villi  are  diffused.  In  ruminants,  the 
villi  are  grouped  at  certain  points.  These  vascular  masses  are 
termed  cotyledons.  The  maternal  cot^'ledons  or  "  buttons " 
form  appendages  or  thickened  points  that  become  greatly  en- 
larged in  the  pregnant  animal. 

Toward  the  end  of  the  pregnant  period,  the  attachments 
between  the  fetal  and  maternal  placentulir  undergo  a  tatty 
degeneration  and  finally  separate.  This  results  in  contractions 
of  the  muscular  wall  of  the  uterus,  and  the  expulsion  of  the  foetus 
and  its  envelopes.  In  the  mare,  it  is  not  uncommon  for  the  colt 
to  be  born  with  the  covering  intact.  This  is  not  common  in  the 
cow.  Usually  the  envelopes  are  not  expelled  until  a  short  time 
after  birth  in  all  animals,  and  it  is  not  uncommon  for  them  to 
be  retained.  This  complication  is  most  commonly  met  with  in 
the  cow. 

In  the  mare  the  retention  of  the  fetal  envelopes  or  "  after- 
birth "  is  commonly  due  to  the  muscles  of  the  womb  not  con- 
tracting properly  following  birth.  Abortion,  especially  the 
infectious  form,  is  commonly  complicated  by  a  retention  of  the 
fetal  membranes.  Any  condition  that  may  produce  an  in- 
flammation of  the  lining  membrane  of  the  womb  may  result  in 
retention  of  the  *'  after-birth."  Injuries  to  the  uterus  resulting 
from  the  animal  slipping,  fighting  and  becoming  crowded  are, 
no  doubt,  common  causes  of  failure  to  "  clean  "  in  cows. 

The  symptoms  are  so  marked  that  a  mistaken  diagnosis  is 
seldom  made.  A  portion  of  the  membranes  is  usually  seen 
hanging  from  the  vulva,  and  the  tail  and  hind  parts  may  be 
more  or  less  soiled.  The  latter  symptom  is  especially  promi- 
nent if  the  membranes  have  been  retained  for  several  days,  and 
decomposition  has  begun.  In  such  case,  the  discharge  from  the 
vulva  is  dark  in  color,  contains  small  pieces  of  the  decomposed 


DISEASES  OF  THE  GENERATIVE  ORGANS  85 

membrane  and  has  a  very  disagreeable  odor.  In  the  mare,  acute 
inflammation  of  the  womb  may  result  if  the  removal  of  the 
'^after-birth"  is  neglected.  Loss  of  appetite,  abnormal  body 
temperature,  weakness  and  diarrhoea  may  follow.  Such  cases 
usually  terminate  in  death.  Retention  of  the  fetal  membranes  is 
a  very  common  cause  of  leucorrhcea. 

Tlie  treatment  consists  in  completely  removing  the  fetal  en- 
velopes soon  after  birth,  unless  they  are  firmly  attached  to  a 
large  surface  .of  the  womb.  When  the  attachments  have  not 
separated,  it  is  not  advisable  to  tear  them  loose  because  of  the 
danger  from  hemorrhage  and  infection,  and  to  avoid  these  com- 
plications special  attention  is  necessary. 

In  the  mare  the  fetal  envelopes  are  usually  removed  within 
a  few  hours  after  birth.  In  the  cow  it  is  not  uncommon  to  wait 
from  twenty-four  to  forty-eight  hours  before  removing  them. 

The  only  successful  method  is  to  remove  them  with  the  hand. 
In  the  large  animals  the  hand  and  arm  is  introduced  into  the 
maternal  passages  and  womb,  and  the  attachments  broken  loose 
with  the  fingers.  Every  precaution  should  be  taken  to  avoid  the 
introduction  of  disease-producing  germs  into  the  parts.  It  is 
advisable  to  flush  out  the  womb  with  a  disinfecting  solution  fol- 
lowing the  removal  of  fetal  envelopes. 

Leucorrhoea. — This  is  a  chronic  inflammation  of  the  mucous 
membrane  lining  the  genital  tract,  that  is  associated  with  more 
or  less  of  a  discharge  from  the  vulva.  It  is  common  in  animals 
that  abort,  or  retain  the  "after-birth." 

The  discharge  may  be  white,  sticky,  albuminous,  and  with- 
out odor,  or  chocolate  colored  and  foul  smelling.  The  tail  and 
hind  parts  are  usually  soiled  with  it.  In  chronic  inflammation 
of  the  womb  the  discharge  is  intermittent.  In  mild  cases  the 
health  of  the  animal  is  in  no  way  impaired.  Sterility  is  com- 
mon.    Loss  of  appetite  and  unthriftiness  occur  in  severe  cases. 

Treatment. — Mild  cases  readily  yield  to  treatment.  This 
consists  in  irrigating  the  maternal  passages  with  a  one-half  per 


86  NON-SPECIFIC  OR  GENERAL  DISEASES 

cent  warm  water  solution  of  liquor  cresolis  compound.  This 
treatment  should  be  repeated  daily  and  continued  for  as  long 
a  time  as  necessary. 

Mammitis. — Inflammation  of  the  mammary  gland  or  udder 
is  more  common  in  the  cow  than  in  any  of  the  other  domestic 
animals.  In  all  animals  it  is  most  frequently  met  with  during 
the  first  few  weeks  after  birth. 

A  predisposing  cause  in  the  deyelopment  of  mammitis  is  a 
high  deyelopment  of  the  mammary  glands.  The  following 
direct  causes  may  1)e  mentioned :  incomplete  milking,  or  milk- 
ing at  irregular  interyals  ;  injury  to  the  udder  by  stepping  on  the 
teat;  blows  from  the  horns  and  pressure  caused  by  lying  on  a 
rough,  uneyen  surface ;  chilling  of  the  udder  by  draughts  and 
lying  on  frozen  ground ;  and  infection  of  the  glandular  tissue 
by  irritating  germs.  The  latter  cause  produces  the  most  serious, 
and,  sometimes,  a  yery  extensiye  inflammation.  This  form  of 
inflammation  may  spread  from  one  cow  to  another,  causing  the 
milk  to  be  unfit  for  food,  and  bringing  about  the  loss  of  one  or 
more  quarters  of  the  udder. 

The  symptoms  occurring  in  the  different  forms  of  mammitis 
differ.  The  inflammation  may  inyolye  one  or  more  of  the  glands, 
and  may  affect  either  the  glandular  or  the  connectiye  tissue. 
In  some  cases  the  gland  may  appear  congested  for  a  few  days 
before  the  inflammatory  changes  occur.  The  part  becomes  hot, 
swollen,  tender  and  reddened.  It  may  feel  doughy  or  hard.  If 
the  connectiye  tissue  is  inyolyed  (interstitial  form),  there  is  apt 
to  be  a  high  body  temperature,  the  udder  may  be  much  larger 
than  normal,  is  tender  and  pits  on  pressure.  Loss  of  appetite 
usually  accompanies  tliis  form  of  mammitis.  Very  little  or  no 
milk  is  secreted.  Sometimes,  the  milk  is  greatly  changed  in 
appearance,  is  foul  smelling  and  contains  pus.  In  congestion  of 
the  udder  and  ruj)ture  of  the  capillary  vessels,  the  milk  may 
contain  blood. 

Mild  inflammation  of  the  udder  responds  readily  to  treat- 


DISEASES  OF  THE  GENERATIVE  ORGANS  87 

ment.  The  interstitial  fonn  may  terminate  in  abscesses  and 
gangrene.  The  replacement  of  the  glandular  tissue  by  fibrous 
tissue  in  one  or  more  quarters  is  not  uncommon.  Death  seldom 
occurs. 

The  preventive  treaiment  consists  in  avoiding  conditions 
that  may  favor  or  cause  an  inflammation  of  the  gland.  Ani- 
mals that  have  highly  developed  mammary  glands  should  be  fed 
a  light  diet  just  before  and  following  parturition.  Following 
parturition,  a  dose  of  Epsom  or  Glauber's  salts  may  be  given. 
If  the  young  does  not  take  all  the  milk,  the  udder  should  be 
milked  out  as  clean  as  possible.  ]\Iassaging  the  udder  by  knead- 
ing or  stroking  may  be  practised. 

The  following  treatment  is  recommended:  The  application 
of  a  thick  coating  of  antiphlogistin  once  or  twice  daily  is  a 
useful  remedy.  If  the  udder  becomes  badly  swollen,  it  should 
be  supported  with  a  bandage.  Extensive  inflammation  may  be 
treated  by  the  application  of  cold  in  the  form  of  packs  of  cracked 
ice.  Irrigating  the  gland  wath  a  four  per  cent  water  solution 
of  boric  acid  is  an  important  treatment  for  certain  forms  of 
mammitis.  Abscess  formation  or  suppuration  should  be 
promptly  treated  by  opening  and  treating  the  abscesses.  If 
gangrene  occurs,  it  may  be  necessary  to  remove  a  part,  or  the 
whole  of  the  udder. 

The  giving  of  milk  discolored  with  blood  may  be  treated  by 
applying  camphorated  ointment  twice  daily. 

Sore  and  Warty  Teats. — Irritation  to  the  teats  by  filth,  cold, 
moisture  and  injuries  cause  the  skin  to  become  inflamed,  sore 
and  scabby. 

Preventive  treatment  is  the  most  satisfactory.  Sore  teats 
may  be  treated  by  applying  the  following  ointment  after  each 
milking:  vaseline  ten  parts  and  oxide  of  zinc  one  part.  Pendu- 
lous warts  may  be  clipped  off  with  a  sharp  pair  of  scissors. 
Castor  oil  applied  to  the  w^art  daily  by  rubbing  may  be  used 
for  the  removal  of  flat  warts. 


88 


NON-SPECIFIC  OR  GENERAL  DISEASES 


"  Milk-fever  "  or  Post-partum  Paralysis. — This  is  a  disease 
peculiar  to  cows,  especially  lieavv  milkers  that  are  in  good 
condition.  It  most  commonly  occurs  after  the  third,  fourth  and 
fifth  calving.  The  disease  usually  appears  within  the  first  two 
or  three  days  after  calving,  but  it  has  been  known  to  occur 
before,  and  as  late  as  several  weeks  after  calving.  The  cause 
is  not  certainly  known.  The  Schmidt  theory  is  that  certain 
toxins  are  fonned  in  the  udder,  owing  to  the  over  activity  of  tlie 
cells  of  the  irlandular  tissue. 


Fig.   20. — A  caye  of  milk-fever. 


The  symptoms  are  characteristic  of  the  disease.  At  the 
very  beginning  of  the  attack  the  cow  stops  eating  and  nmiinat- 
ing,  becomes  uneasy,  switches  the  tail,  stamps  the  feet,  trembles, 
staggers  when  forced  to  walk  and  finally  falls  and  is  unable  to 
get  up.  At  first  she  may  lie  in  a  natural  position;  later,  as  the 
paralytic  symptoms  become  more  pronounced,  the  head  is  laid 
against  the  side  of  the  body  and  the  animal  seems  to  be  in  a  deep 
sleep  (Fig.  20).  In  the  more  severe  form  the  cow  lies  on  her 
side,  consciousness  is  lost  and  the  paralysis  of  the  muscles  is 


DISEASES  OF  THE  GENERATIVE  ORGANS 


89 


marked.  The  different  body  functions  are  interfered  with; 
the  urine  is  retained,  bloating  occurs,  respirations  are  slow, 
pulse  weak  and  temperature  subnormal  or  normal. 

Preventive  treatment,  such  as  feeding  a  spare  diet  during 
the  latter  period  of  pregnancy,  is  not  always  advisable.  Heavy 
milkers  should  be  given  one-half  pound  of  Glauber's  salts  a  day 
or  two  before  calving,  and  the  dose  repeated  when  the  cow  be- 
comes fresh.  Cows  affected  with  milk-fever  seldom  die  if 
treated  promptly. 

The  treatment  consists  in  empty- 
ing the  udder  by  milking  and 
injecting  air  or  oxygen  gas  into 
the  gland  until  it  is  completely 
distended  (Fig.  21).  The  milk- 
fever  apparatus  should  be  clean, 
and  the  air  injected  filtered.  Be- 
fore introducing  the  milking  tube 
into  the  milk  duct,  the  udder  should 
first  be  washed  with  a  disinfectant, 
and  a  clean  towel  laid  on  the  floor 
for  the  gland  to  rest  on.  After 
injecting  the  quarter,  strips  of 
muslin  or  tape  should  be 
around  the  ends  of  the  teats  to  pre- 
vent the  escape  of  the  air.  If  the  cow  does  not  show  indications 
of  recovery  in  from  four  to  five  hours,  the  treatment  should  be 
repeated. 

It  is  very  necessary  to  give  the  cow  a  comfortable  stall  and 
protect  her  from  any  kind  of  exposure.  ^N^o  bulky  drenches 
should  be  administered.  If  she  lies  stretched  out,  the  fore  parts 
should  be  raised  by  packing  straw  under  her.  This  is  necessary 
in  order  to  prevent  pneumonia,  caused  by  regurgitated  feed 
entering  the  air  passages  and  lungs.  It  is  very  advisable  to 
give  her  the  following  mixture  for  a  few  days  after  the  attack: 


Fig.      21. — Milk-fever      apparatus: 
tied     (A)  pump;  (B)  filter;  (C)  rubber  tub- 
ing; and  (D)  milk  tube. 


90  NON-SPECIFIC  OR  GENERAL  DISEASES 

tincture  of  mix  vomica  two  ounces,  and  alcohol  six  ounces.     One 

ounce  of  this  mixture  may  be  given  four  times  daily  in  a  little 

water. 

QUESTIONS 

1.  Name  the  generative  organs  of  the  female. 

2.  Name  the  generative  organs  of  the  male. 

3.  Give  the  causes  of  sterility  or  impotency  in  the  male  and  female. 

4.  Give  the  treatment  of  impotency  in  the  male  and  female. 

5.  Describe  the  probable  signs  of  pregnancy;  positive  signs  of  pregnancy. 

6.  Describe  the  liygienic  care  of  tlie  pregnant  female  in  a  general  way. 

7.  Name  the  different  forms  of  abortion;  give  the  causes. 

8.  Describe  the  preventive  treatment  of   infectious   abortion. 

9.  Give  a  general  discussion  of  the  physiology  of  parturition. 

10.  What  are  tlie  common  causes  of  difficult  birth? 

11.  What  parts  of  the  foetus  may  present  themselves  at  the  inlet  of  the 

pelvic  cavity?     What  are  the  different  positions  of  the  foetus? 

12.  What  attention  sliould  be  given  the  mother  at  the  time  of  parturition? 

13.  \Miat  attention  sliould  be  given  the  young  immediately  after  birth? 

14.  Give  the  causes  of  retention  of  the  fetal  membranes;  state  the  method 

of  removing  them. 

15.  Give  the  causes  and  treatment  of  inflammation  of  the  udder. 
IG.  Give   the  cause  of   milk- fever;    give  the  treatment. 


CHAPTER  VIII 
DISEASES  OF  THE  RESPIRATORY  APPARATUS 

General  Discussion. — The  respiratory  apparatus  may  be 
divided  into  two  groups  of  organs,  anterior  and  posterior.  The 
anterior  group,  the  nostrils^  nasal  cavities,  jAarynx,  lanjnx  and 
trachea,  is  situated  in  the  region  of  the  head  and  neck.  The 
posterior  group,  the  bronchial  tubes  and  lungs,  is  situated  in 
the  chest  or  thoracic  cavity. 

The  nostrils  are  the  anterior  openings  of  the  air  j)assages. 
The  nasal  cavities  are  situated  in  the  anterior  region  of  the 
head,  and  extend  the  entire  length  of  the  face.  Each  cavity 
is  divided  into  three  long,  narrow  passages  by  the  two  pairs  of 
turbinated  bones.  The  lining  membrane  is  the  nasal  mucous 
membrane,  the  lower  two-thirds  or  respiratory  portion  differing 
from  the  upper  one-third,  in  that  the  latter  j^ossesses  the  nerve 
endings  of  the  olfactory  nerve  and  is  the  seat  of  smell.  The 
five  pairs  of  head  sinuses  communicate  with  the  nasal  cavities. 
Posteriorly  and  near  the  superior  extremity  of  the  nasal  passages, 
are  two  large  openings,  the  guttural,  that  open  into  the  pharyn- 
geal cavity. 

The  pharynx  is  a  somewhat  funnel-shaped  cavity.  The 
walls  are  thin  and  formed  by  muscles  and  mucous  membrane. 
This  is  the  cross-road  between  the  digestive  and  respiratory 
passages.  In  the  posterior  portion  of  the  cavity  there  are  two 
openings.  The  inferior  opening  leads  to  the  larynx  and  the 
superior  one  to  the  oesophagus.  All  feed  on  its  way  to  the 
stomach  must  pass  over  the  opening  into  the  larynx.  It  is 
impossible,  however,  for  the  feed  to  enter  this  opening,  unless 
accidentally  when  the  animal  coughs.  The  cartilage  closing  this 
opening  is  pressed  shut  by  the  base  of  the  tongue  when  the  bolus 
of  feed  is  passed  back  and  into  the  oesophageal  opening. 

91 


92  NON-SPECIFIC  OR  GENERAL  DISEASES 

TJie  larynx  may  be  compared  to  a  box  open  at  both  ends. 
The  several  cartilages  that  form  it  are  united  by  ligaments.  It 
is  lined  by  a  mucous  membrane.  The  posterior  extremity  is 
united  to  the  first  cartilaginous  ring  of  the  trachea.  The 
anterior  opening  is  closed  by  the  epiglottis.  Just  within  is  a 
\'-shaped  opening  that  is  limited  laterally  by  the  folds  of  the 
laryngeal  mucous  membrane,  the  vocal  chords. 

The  tracliea  is  a  cylindrical  tube  originating  at  the  posterior 
extremity  of  the  larynx,  and  terminating  within  the  chest  cavity 
at  a  point  just  above  the  heart  in  the  right  and  left  bronchial 
tubes.  It  is  formed  by  a  series  of  cartilaginous  rings  joined 
together  at  their  borders  by  ligaments  and  lined  by  a  mucous 
membrane. 

The  hronchial  tuhes  resemble  the  trachea  in  structure.  They 
enter  the  lungs  a  short  distance  from  their  origin,  where  they 
subdivide  into  branches  and  sub-branches,  gradually  decreasing 
in  calibre  and  losing  the  cartilaginous  rings,  ligaments  and 
muscular  layer  until  only  the  thin  mucous  membrane  is  left. 
They  become  capillary  in  diameter,  and  finally  open  into  the 
infundibula  of  the  air  cells  of  the  lungs. 

The  lungs  take  up  all  of  the  space  in  the  thoracic  cavity  not 
occupied  by  the  heart,  blood-vessels  and  oesophagus.  This  cavity 
resembles  a  cone  in  shape  that  is  cut  obliquely  downwards  and 
forward  at  its  base.  The  base  is  formed  by  the  diaphragm  which 
is  pushed  forward  at  its  middle.  It  is  lined  by  the  pleura,  a 
serous  membrane,  that  is  inflected  from  the  wall  over  the  differ- 
ent organs  within  the  cavity.  The  median  folds  of  the  pleura 
divide  the  cavity  into  right  and  left  portions.  A  second  method 
of  describing  the  arrangement  of  the  pleura  is  to  state  that  it 
f()i"ms  two  sacks,  right  and  left,  that  enclose  the  lungs.  The 
lungs  are  the  essential  organs  of  respiration.  The  tissue  that 
forms  them  is  light,  will  float  in  water,  is  elastic  and  somewhat 
rose-colored.  Each  lung  is  divided  into  lobes,  and  each  lobe  into 
a  great  number  of  lobules  by  the  supporting  connective  tissue. 


DISEASES  OF  THE  RESPIRATORY  APPARATUS  93 

The  lobule  is  the  smallest  divisiuu  of  the  luug  and  is  formed 
by  capillary  bronchial  tubes,  air  cells  and  blood-vessels.  It  is 
here  that  the  external  respiration  or  the  exchange  of  gases  be- 
tween the  capillaries  and  the  air  cells  occurs. 

Ventilation. — It  is  agreed  by  all  persons  who  have  investi- 
gated the  subject,  that  unventilated  stable  air  is  injurious  to 
animals.  At  one  time  it  was  believed  that  the  injurious  effects 
resulting  from  the  breathing  of  air  charged  with  gases  and 
moisture  from  the  expired  air  and  the  animal's  surroundings, 
were  due  to  a  deticiency  in  oxygen.  It  is  now  l)elieved  that  the 
ill-effects  are  mainly  due  to  the  stagnation  of  air,  the  humid 
atmosphere,  and  the  irritating  gasee  emanating  from  the  body 
excretions. 

The  common  impurities  for^d  in  stable  air  are  carbonic  and 
ammonia  gas,  moisture  charged  with  injurious  matter  and  dust 
from  the  floor  and  bodies  of  the  animals.  As  a  rule,  the  more 
crowded  and  filthy  the  stable,  the  more  impurities  there  are  in 
the  air.  If  any  of  the  animals  are  affected  with  an  infectious 
disease,  such  as  tuberculosis  or  glanders,  the  moisture  and  dust 
may  act  as  carriers  of  the  disease-producing  germs.  Infectious 
diseases  spread  rapidly  in  crowded,  poorly  ventilated  stables. 
The  two  factors  responsible  for  this  rapid  spread  of  disease  are 
the  lowered  vitality  of  the  animal,  due  to  breathing  the  vitiated 
air,  and  the  greater  opportunity  for  infection,  because  of  the 
comparatively  large  number  of  bacteria  present  in  the  air. 

The  purpose  of  stable  ventilation  is  to  replace  the  stable 
air  with  purer  air.  The  frequency  with  which  the  air  in  the 
stable  should  be  changed  depends  on  the  cubic  feet  of  air  space 
provided  for  each  animal,  and  the  sanitary  conditions  present. 
The  principal  factor  in  stable  ventilation  is  the  force  of  the 
wind.  In  cold  weather  it  is  very  difficult  to  properly  ventilate 
a  crowded  stable  without  too  much  loss  of  animal  heat  and 
creating  draughts. 

For  practical  purposes,  the  need  of  ventilation  in  a  stable 


94 


NON-SPECIFIC  OR  GENERAL  DISEASES 


can  be  determined  bj  the  odor  of  the  air,  the  amount  of  moisture 
present  and  the  temperature.  It  is  impossible  to  keep  the  air 
witliin  the  stable  as  pure  as  the  atmosphere  outside. 

All  dangers  from  injury  by  breathing  impure  air,  or  by 
draughts  can  be  eliminated  by  proper  stable  construction,  atten- 
tion to  the  ventilation  and  keeping  the  quarters  clean. 

Catarrh  (Cold  in  the  Head). — Catarrh  is  an  inflammation 


Fig.  22. — A  case  of  catarrhal  cold. 

of  the  mucous  membrane  lining  the  nasal  cavities  that  usually 
extends  to  the  membrane  lining  of  the  sinuses  of  the  head.  It 
may  be  acute  or  chronic.  The  inflammation  very  often  extends 
to  the  pharynx  and  larynx.  Cold  in  the  head  is  more  common 
in  the  horse  than  in  any  of  the  other  animals  (Fig.  22). 

The  most  common  causes  of  ''  colds  "  are  standing  or  lying 
in  a  draught,  becoming  wet,  and  exposure  to  the  cold.  "  Colds  " 
are  common  during  cold,  changeable  v^^eather.     Horses  that  are 


DISEASES  OF  THE  RESPIRATORY  APPARATUS  95 

accustomed  to  warm  stables,  are  very  apt  to  take  "  cold  "  if 
changed  to  a  cold  stable  and  not  protected  with  a  blanket.  .Most 
animals  are  not  affected  by  the  cold  weather  if  given  dry  quarters 
and  a  dry  bed.  Irritation  to  the  mucous  membrane  by  dust, 
gases  and  germs  is  a  common  cause.  Influenza  and  colt  dis- 
temper are  characterized  by  an  inflammation  of  the  respiratory- 
mucous  membranes.  In  the  horse,  chronic  catarrh  is  commonly 
caused  by  diseased  teeth,  and  injuries  to  the  wall  of  the  maxillary 
sinus.    In  sheep,  the  larva3  of  the  bot-fly  may  cause  catarrh. 

The  early  symptoms  usually  pass  unnoticed  by  the  attendant. 
The  lining  membrane  of  the  nostrils  is  at  first  dry  and  red. 
During  this  stage  sneezing  is  common.  In  a  few  days  a  dis- 
charge appears.  This  is  watery  at  first,  but  may  become 
catarrhal,  heavy,  mucous-like  and  turbid.  In  severe  cases  it 
resembles  pus.  The  lining  membrane  of  the  eyelids  appears  red 
and  tears  may  flow  from  the  eye.  Sometimes  the  animal  acts 
dull  and  feverish,  but  this  symptom  does  not  last  longer  than 
one  or  t^vo  days  unless  complicated  by  sore  throat. 

Iiifiammation  of  the  throat  is  a  common  complication  of 
"  colds."  It  is  characterized  by  difficulty  in  swallowing  and 
partial,  or  complete  loss  of  appetite.  Drinking  or  exercising 
causes  the  animal  to  cough.  If  the  larynx  as  well  as  the  pharynx 
is  inflamed,  distressed  and  noisy  breathing  may  occur.  Pressure 
over  the  region  of  the  throat  causes  the  animal  pain. 

Common  "  cold "  terminates  favorably  within  a  week. 
Chronic  catarrh  may  persist  until  the  cause  is  removed  and  the 
necessary  local  treatment  applied.  Inflammation  of  the  pharynx 
and  larynx  may  persist  for  several  weeks  unless  properly  treated. 
Abscesses  may  fonn  in  the  region  of  the  throat.  Horses  fre- 
quently become  thick  winded  as  a  result  of  severe  attacks  of 
sore  throat. 

The  treatment  is  both  preventive  and  curative.  "  Colds  " 
and  sore  throat  can  be  largely  prevented  by  good  care,  exercise 
and  properly  ventilated  stables.    Mild  cases  require  a  light  diet, 


96  NON-SPECIFIC  OR  GENERAL  DISEASES 

comfortable  quarters  and  a  dry  bed.  Allowing  the  animal  to 
inhale  steam  three  or  four  times  daily  is  useful  in  relieving 
the  inflammation.  Easily  digested  feeds,  and  in  case  the  animal 
has  dilKculty  in  s\vallowing,  soft  feeds  and  gruels,  should  be 
given.  The  throat  may  be  kept  covered  with  a  layer  of  anti- 
phlogistin  and  bandaged.  Glycoheroin  may  be  given  in  from 
teaspoonful  to  tablespoonful  doses,  depending  on  the  size  of 
the  animal.  Chlorate  of  potassium  may  be  given  in  the  drink- 
ing water. 

If  the  animal  becomes  run  down  in  flesh,  as  sometimes  occurs 
in  chronic  catarrh,  bitter  tonics  should  be  given.  In  the  latter 
disease,  it  is  sometimes  necessary  to  trephine  and  wash  out  the 
sinus  or  sinuses  afi"ected  with  an  antiseptic  solution.  It  may  be 
necessary  to  continue  this  treatment  for  several  weeks. 

Bronchitis. — Inflammation  of  the  bronchial  tubes  may  be 
either  acute  or  chronic.  Acute  bronchitis  is  especially  common 
in  the  horse,  while  the  chronic  form  is  more  often  met  with  in 
the  smaller  animals,  especially  hogs.  This  disease  is  most 
common  among  horses  during  the  changeable  seasons  of  the 
years.  It  is  caused  by  warm,  close  stables  or  stalls,  and  irritating 
gases  emanating  from  the  floor,  or  manure  in  the  stall.  In 
general,  the  causes  are  about  the  same  as  in  cold  in  the  head. 
In  young  animals  and  hogs,  the  inhalation  of  dust,  and  bronchial 
and  lung  worms  commonly  cause  it.  Verminous  bronchitis 
usually  becomes  chronic. 

In  the  acute  form  of  the  disease  the  symptoms  come  on  very 
quickly,  the  fever  is  high  and  the  pulse  beats  and  respirations 
are  rapid.  Chilling  of  the  body  occurs,  and  the  animal  may 
appear  dull  and  refuse  to  eat.  The  animal  coughs  frequently. 
Ivecovery  occurs  within  a  few  days,  unless  complicated  by  sore 
throat  and  pneumonia.  In  the  horse,  bronchitis  is  not  a  serious 
disease,  but  in  other  animals  recovery  is  delayed  and  complica- 
tions are  more  common. 

In  chronic  hroncliitis  in  the  horse,  the  animal  coughs  fre- 


DISEASES  OF  THE  RESPIRATORY  APPARATUS  97 

quently,  there  is  more  or  less  discharge  from  the  nostrils  and 
the  respirations  may  hecome  labored  when  exercised.  The  ani- 
mal is  usually  weak,  in  poor  flesh  and  unfit  for  work.  In  other 
cases,  symptoms  of  broken  wind  are  noticed.  Severe  coughing 
spells  on  getting  up  from  the  bed,  or  on  moving  about  are  char- 
acteristic of  bronchitis  in  hogs.  Verminous  bronchitis  in  calves 
and  lambs  is  characterized  by  severe  spells  of  coughing,  difficult 
and  labored  breathing  and  a  weak,  emaciated  condition. 

The  preventive  treatment  is  the  same  as  for  "  colds."  In 
the  acute  form  the  treatment  consists  largely  in  careful  nursing. 
Properly  ventilated,  clean  quarters  that  are  free  from  dust  should 
be  provided.  The  animal  should  be  covered  with  a  light  or 
heavy  blanket,  depending  on  the  temperature  of  the  stable,  and 
the  limbs  bandaged.  A  light  diet  should  be  fed  for  a  few  days. 
It  is  advisable  to  give  the  animal  a  physic  of  oil.  The  inhalation 
of  steam  every  few  hours  during  the  first  few  days  should  be 
practised.    Glycoheroin  may  be  given  three  or  four  times  a  day. 

Animals  affected  with  chronic  bronchitis  should  not  be 
exercised  or  worked.  We  should  guard  against  their  taking 
cold,  give  nourishing  feeds,  and  a  tonic  if  necessary. 

Congestion  of  the  Lungs. — Pulmonary  congestion  is  gener- 
ally due  to  overexertion  and  exposure  to  extreme  heat  or  cold. 
It  may  occur  if  the  animal  is  exercised  when  sick  or  exhausted. 
Hogs  that  are  heated  from  exercise  and  allowed  access  to  cold 
water,  may  suffer  from  a  congestion  or  engorgement  of  the 
lungs.  It  may  be  present  at  the  beginning  of  an  attack  of 
pneumonia  or  pleurisy. 

The  symptoms  are  difficult  breathing  and  the  animal  fights 
for  its  breath.  The  body  temperature  may  be  several  degrees 
above  the  normal.  In  the  mild  form,  the  above  symptoms  are  not 
so  marked;  The  onset  and  course  of  the  disease  are  rapid, 
recovery,  pneumonia,  or  death  often  occurring  within  twenty- 
four  hours. 

Pulmonary  hemorrha(jc  is  not  uncommon.     The  discharge 
7 


98  NON-SPECIFIC  OR  GENERAL  DISEASES 

from  tlie  nostrils  may  be  slightly  tinged  with  blood,  or  there 
may  be  an  intermittent  discharge  of  blood  from  the  nostrils  or 
mouth.  The  mucous  membranes  are  pale,  the  animal  trembles 
and  shows  marked  dyspnoea. 

The  preventive  treatment  consists  in  using  the  proper  judg- 
ment in  caring  for,  and  in  working  or  exercising  animals.  This 
is  especially  true  if  the  animal  is  affected  with  acute  or  chronic 
disease.  At  the  very  beginning,  bleeding  should  be  practised. 
Hot  blankets  renewed  frequently  and  bandages  to  the  limbs  is 
a  very  necessary  part  of  the  treatment.  In  case  of  severe  pul- 
monary hemorrhage,  treatment  is  of  little  use. 

Pneumonia. — Inflammation  of  the  lungs  is  more  common 
in  horses  than  in  any  of  the  other  domestic  animals.  The 
croupous  form  is  the  most  common.  The  inflammation  may 
affect  one  or  both  lungs,  one  or  more  lobes,  or  scattered  lobules 
of  lung  tissue.  The  inflammation  may  be  acute,  subacute  or 
chronic. 

The  causes  are  very  much  the  same  as  in  other  respiratory 
diseases.  Exposure  to  cold  and  wet,  stable  draughts,  becoming 
chilled  after  perspiring  freely  and  washing  the  animal  with 
cold  water  are  the  common  causes  of  pneumonia.  Inflammation 
of  the  lungs  is  especially  apt  to  occur  if  the  animal  is  not 
accustomed  to  such  exposure.  Animals  affected  with  other 
respiratory  diseases  are  predisposed  to  pneumonia.  Drenching 
animals  by  way  of  the  nostril  and  irritating  drenches,  or  re- 
gurgitated feed  passing  into  the  air  j)assages  and  lungs  are  the 
traumatic  causes  of  pneumonia. 

The  symptoms  vary  in  the  different  forms  of  pneumonia. 
In  case  pneumonia  occurs  secondarily,  the  earliest  symptoms 
are  confounded  with  those  of  the  primary  disease.  The  first 
symptoms  noticed  may  be  a  high  body  temperature,  as  indicated 
by  chills,  and  refusing  to  eat.  The  visible  mucous  membranes 
are  red  and  congested,  the  nostrils  dilated,  the  respirations 
quickened  and  difficult,  the  expired  air  hot  and  the  pulse  beats 


DISEASES  OF  THE  RESPIRATORY  APPARATUS  99 

accelerated.  The  animal  coughs,  and  in  the  horse,  a  rusty 
discharge  may  be  noticed  adhering  to  the  margins  of  the  nostrils. 
The  horse  refuses  to  lie  down  if  both  lungs  are  inflamed.  In 
severe  cases  the  expression  of  the  face  indicates  pain,  the  respira- 
tions are  labored,  the  general  symptoms  aggTavated,  and  the 
animal  stands  with  the  front  feet  spread  apart.  Cattle  are  in- 
clined to  lie  down,  unless  the  lungs  are  seriously  affected.  ITogs 
like  to  burrow  under  the  litter. 

The  course  of  croupous  pneumonia  is  typical,  and  unless 
it  terminates  fatally  in  the  first  stage,  the  periods  of  congestion, 
hepatization  and  resolution  follow  each  other  in  regular  manner. 
Auscultation  of  the  lungs  is  of  gTeat  value  in  diagnosing  and 
watching  the  progTess  of  the  disease.  It  is  more  difficult  to 
determine  the  character  of  the  lung  sounds  in  the  horse  and  cow 
than  it  is  in  the  small  animals.  This  is  especially  difficult  if  the 
animal  is  fat.  During  the  period  of  congestion  which  lasts 
about  a  day,  one  can  hear  both  healthy  and  crepitating  sounds. 
The  period  of  hepatization  is  characterized  by  an  absence  of 
sound  over  the  diseased  area.  The  inflammatory  exudates  be- 
come organized  at  the  beginning  of  this  stage,  and  the  air  can  not 
enter  the  air  cells.  This  period  lasts  several  days.  Resolution 
marks  the  beginning  of  recovery  or  convalescence.  Toward  the 
end  of  the  second  period,  the  inflammatory  exudate  in  the  air 
cells  has  begun  to  degenerate.  In  the  last  stage,  these  exudates 
undergo  liquefaction  and  are  absorbed,  or  expelled  by  coughing, 
in  from  seven  days  to  two  weeks,  depending  on  the  extent  of  the 
inflammation  and  the  general  condition  of  the  animal. 

In  the  subacute  form  the  symptoms  are  mild  and  may  sub- 
side within  a  w^eek.  Sometimes  abscesses  form  in  the  lung. 
Gangrenous  inflammation  of  the  lung  can  be  recognized  by  the 
odor  of  the  expired  air  and  the  severity  of  the  symptoms.  This 
form  of  pneumonia  terminates  fatally.  If  the  larger  portion 
of  the  lung  tissue  is  inflamed,  death  from  asphyxia  may  occur 
in  the  second  stage. 


100  NON-SPECIFIC  OR  GENERAL  DISEASES 

The  success  in  the  treatment  of  pneumonia  depends  largely 
on  the  care.  Properly  ventilated,  clean,  comfortable  quarters 
and  careful  nursing  are  highly  important.  Large  animals 
should  be  given  a  roomy  box  stall.  Cold  does  not  aggravate 
pneumonia,  providing  the  animal's  body  is  well  protected  with 
blankets  and  the  limbs  bandaged.  Wet,  damp  quarters  and 
draughts  are  injurious.  Hogs  should  be  given  plenty  of  bedding 
to  burrow  in.  A  light,  easily  digested  diet  should  be  fed.  Very 
little  roughage  should  be  fed.  If  the  animal  does  not  eat  well, 
it  may  be  given  eggs  and  milk.  Weak  pulse  beats  should  be 
treated  by  giving  digitalis  and  strychnine.  Counterirritation 
to  the  chest  wall  is  indicated.  During  convalescence,  bitter 
tonics  may  be  given.  Constipation  should  be  treated  by  giving 
the  animal  castor  or  linseed  oil. 

Pleurisy. — Inflammation  of  the  pleura  is  most  common  in 
horses.  It  occurs  in  all  farm  animals  and  is  frequently  uni- 
lateral. There  are  two  forms  of  pleurisy,  acute  and  chronic. 
Pleuropneumonia  is  common  when  the  cause  is  a  specific  germ. 
This  occurs  in  tuberculosis,  pleuroj^neumonia  of  horses  and 
pneumococcus  infection. 

The  common  causes  are  exposure  to  cold,  chilling  winds, 
draughty,  damp  quarters,  and  drinking  cold  water  when  perspir- 
ing. Injuries  to  the  costal  pleura  by  fractured  ribs  and  punc- 
tured wounds  may  cause  it  to  become  inflamed. 

The  early  symptoms  of  acute  pleurisy  are  chills,  rise  in 
body  temperature,  pain  and  abdominal  breathing.  The  most 
characteristic  symptom  is  the  ridge  extending  along  the  lower 
extremities  of  the  ribs  (pleuritic  ridge).  The  animal  does  not 
stand  still  as  in  pneumonia,  but  changes  its  position  occasionally, 
its  movements  in  many  cases  being  accompanied  by  a  grunt. 
Pressure  on  the  wall  of  the  chest  causes  the  animal  to  flinch 
and  show  evidence  of  severe  pain.  Large  animals  rarely  lie 
down.  The  cough  is  short  and  painful.  On  placing  the  ear 
against  the  wall  of  the  chest  and  listening  to  the  respirations, 


DISEASES  OF  THE  RESPI'R'ATORY  APPARATUS  101 

we  are  able  to  hear  friction  sounds.  After  a  few  ^ays  effusion 
occurs  in  the  pleural  cavity.  Although  the  animal  may  have 
refused  to  eat  up  to  this  time,  it  now  appears  greatly  relieved 
and  may  offer  to  eat  its  feed.  This  relief  may  be  only  tem- 
porary. If  the  fluid  exudate  forms  in  sufficient  quantity  to  cause 
pressure  on  the  heart  and  lungs  and  interfere  with  their  move- 
ment, the  pulse  beat  is  weak,  the  respirations  quick  and  labored, 
the  elbows  are  turned  out  and  the  feet  are  spread  apart,  xill 
of  the  respiratory  muscles  may  be  used.  The  expression  of  the 
face  may  indicate  threatened  asphyxia.  We  may  determine  the 
extent  of  the  pleural  exudate  by  auscultation.  There  is  no 
evidence  of  respiratory  sounds  in  that  portion  of  the  chest  below 
the  surface  of  the  fluid.  Dropsical  swellings  may  occur  on 
the  under  surface  of  the  breast  and  abdomen. 

In  subacute  cases  evidence  of  recovery  is  noted  in  from  four 
to  ten  days.  Acute  pleurisy  very  often  terminates  fatally. 
Under  the  most  favorable  conditions,  recovery  takes  place  very 
slowly,  sometimes  extending  over  a  period  of  several  months. 
It  is  not  uncommon  for  the  horse  to  continue  having  ''  defective 
wind." 

The  treatment  consists  in  good  care,  well  ventilated  quarters 
and  careful  nursing,  the  same  as  recommended  in  the  treatment 
of  pneumonia.  At  the  very  beginning,  the  pain  may  be  re- 
lieved by  the  administration  of  small  doses  of  morphine.  If 
the  conditions  in  the  stable  permit,  a  hot  blanket  that  has  been 
dipped  in  hot  water  and  wrung  out  as  dry  as  possible,  may  be 
applied  to  the  chest  wall  and  covered  with  a  rubber  blanket. 
This  treatment  should  be  continued  during  the  first  few  days 
of  the  inflammation.  These  applications  may  be  reinforced 
by  occasionally  applying  mustard  paste  to  the  sides  of  the  chest. 

The  animal  should  be  allowed  to  drink  but  a  limited  amount 
of  water.  The  feed  must  be  highly  nutritious.  Milk  and  eggs 
should  be  given  if  necessary.  A  laxative  dose  of  oil  should  be 
given.    Calomel,  aloes,  and  digitalis  are  recommended  when  the 


102  NQN-SPECIPIC  OR  GENERAL  DISEASES 

effusion  period  approaches  in  order  to  increase  the  elimination 
of  fluid,  and  lessen  its  entrance  into  the  body  cavity.  If  the 
amount  of  effusion  is  large,  puncture  of  the  thoracic  cavity  with 
a  trocar  and  cannula  may  be  practised.  This  operation  should 
be  performed  carefully,  and  all  possible  precautions  used  against 
infection  of  the  wound.  During  the  later  period  of  the  disease 
iodide  of  potassium,  iron  and  bitter  tonics  should  be  given. 

Broken-wind,  Heaves. — The  terms  broken-wind  and  heaves 
are  used  in  a  way  to  include  a  number  of  different  diseases  of 
the  respiratory  organs  of  the  horse.  The  term  heaves  is  applied 
almost  wholly  to  an  emphysematous  condition  of  the  lungs. 
Broken-wind  may  include  the  following  diseased  conditions : 
obstruction  of  the  nasal  passages  by  bony  enlargements  and 
tumors ;  tumors  in  the  pharynx ;  enlarged  neck  glands ;  collection 
of  pus  in  the  guttural  pouches  and  paralysis  of  the  left,  or  both 
recurrent  nerves  (roaring). 

The  common  causes  of  heaves  are  pre-existing  diseases  of 
the  respiratory  organs,  severe  exercise  when  the  animal  is  not 
in  condition  and  wrong  methods  of  feeding.  Heaves  is  more 
common  in  horses  that  are  fed  heavily  on  dusty  timothy  and 
clover  hay  and  allowed  to  drink  large  quantities  of  water  after 
feeding,  than  in  horses  that  are  fed  green  feeds,  graze  on 
pastures  or  receive  prairie  hay  for  roughage.  Chronic  indiges- 
tion seems  to  aggravate  the  disease.  Over-distention  of  the 
stomach  and  intestines  due  to  feeding  too  much  roughage  and 
grain  interferes  with  respiration.  Severe  exercise  when  in  this 
condition  may  result  in  over-distention,  dilation  and  rupture  of 
the  air  cells.  This  is  the  most  common  structural  change  met 
with  in  the  lungs  of  horses  affected  with  heaves.  It  is  termed 
emphysema. 

The  common  symptoms  noted  are  the  double  contraction  of 
the  muscles  of  the  flank  with  each  expiration,  a  short,  dry  cough 
and  the  dilated  nostrils.  The  frequent  passage  of  gas  is  a  promi- 
nent symptom   in  well-estal)lislicd  cases   of  heaves.      Chronic 


DISEASES  OF  THE  RESPIRATORY  APPARATUS  103 

indigestion  is  commonly  present  in  heavy  horses  that  are  not 
well  cared  for,  or  are  given  hard  work.  This  condition  aggra- 
vates the  distressed  breathing. 

Heaves  is  a  pennanent  disorder,  but  it  may  be  relieved  by 
climatic  changes  and  careful  attention  to  the  animal's  diet. 

The  following  preventive  treatment  is  recommended :  Dusty 
hay  should  not  be  fed  to  horses.  Clover  hay  is  not  a  safe  feed 
for  horses  that  are  worked  hard.  When  starting  on  a  drive 
after  feeding,  the  horse  should  not  be  driven  fast,  but  allowed 
to  go  slowly  for  a  few  miles. 

The  symptoms  can  be  greatly  relieved  by  careful  attention 
to  the  diet.  A  limited  quantity  of  roughage  should  be  fed,  and 
this  should  be  good  in  quality  and  fed  in  the  evening.  During 
the  warm  weather,  the  animal  should  be  watered  frequently. 
After  quitting  work  in  the  evening  the  animal  may  be  allowed 
to  drink  as  much  water  as  it  wants.  Plenty  of  grain,  soft  feed 
and  roots  may  be  fed.  A  small  handful  of  flaxseed  meal  given 
with  the  feed  helps  in  keeping  down  constipation.  Fowler's 
solution  of  arsenic  may  be  given  twice  daily  with  the  feed,  in 
half-ounce  doses  for  a  period  of  ten  days  or  two  weeks.  Chronic 
indigestion  should  be  combated  by  digestive  tonics. 

QUESTIONS 

1.  Name  the  organs  that  form  the  anterior  and  posterior  air  passages. 

2.  To  what  conditions  are  the  injurious   effects  of  keeping  animals   in   a 

poorly  ventilated  stable  due? 

3.  State  the  purpose  of  ventilation.     How  can  the  need  of  ventilation  be 

determined  in  a  stable? 

4.  State  the  causes  of  "  cold"  in  the  head;  give  the  treatment. 

5.  State  the  cause  of  bronchitis ;  give  the  treatment. 

6.  What    are    the    causes    of    pneumonia?      Describe    the    symptoms    and 

treatment. 

7.  What   symptoms   are   characteristic   of   pleurisy?      Give   the   treatment 

for  pleurisy. 

8.  Give  the  causes  and  treatment  of  "  heaves." 


CHAPTER   IX 


h 


M 


DISEASES  OF  THE  CIRCULATORY  ORGANS 

General  Discussion, — The  circulatory  organs  are  the  heart, 
arteries,  veins  and  lymphatics.  The  heart  is  the  central  organ 
of  the  circulatory  system  (Fig.  23).  Its  function  is  to  force 
the  blood  through  the  blood-vessels.  It  is  situated  in  the  thoracic 
cavity  between  the  lungs,  and  enclosed  by  a  special  fold  of  the 

^______^ __,  pleura,  the  pericardial 

sack.  There  are  two 
kinds  of  blood-vessels, 
arteries  and  veins. 
The  arteries  leave  the 
heart  and  carry  the 
blood  to  the  many  dif- 
ferent organs  of  the 
body.  The  veins  re- 
turn to  the  heart  and 
carry  the  blood  from 
the  body  tissues.  The 
capillaries  are  small 
blood-vessels,  micro- 
scopic in  size,  that  con- 
nect the  arteries  with 
the  veins.  The  arte- 
ries carry  the  ]iure 
blood.  The  opposite  is  true,  however,  of  the  lesser  or  pul- 
monary system.  The  pulmonary  artery  carries  the  impure 
blood  to  the  lungs,  and  the  pulmonary  veins  carry  the  pure  blood 
back  from  the  lungs.  The  Ijimpliatic  vessels  carry  a  transparent 
or  slightly  colored  fluid  and  chyle  from  the  tissues  and  ali- 
mentary canal.  This  system  of  vessels  empties  into  the  venous 
system. 
104 


Fig.  23. — Photograph  of  model  of  horse's  heart: 
(A)  auricle;  (B)  ventricle;  (C)  pulmonary  artery; 
(F)  pulmonary  veins;  (D)  posterior  aorta;  and  (E) 
anterior  aorta. 


DISEASES  OF  THE  CIRCULATORY  ORGANS  105 

The  functions  of  the  blood  arc  to  nourish  the  body  tissues; 
furnish  material  for  the  purpose  of  the  body  secretions ;  supply 
the  cells  of  the  body  with  oxygen;  convey  from  the  tissues 
injurious  substances  produced  by  the  cellular  activity;  and 
destroy  organisms  that  may  have  entered  the  body  tissues.  The 
cellular  and  fluid  portions  of  the  blood  are  not  always  destruc- 
tive to  disease-producing  organisms.  In  certain  infectious  dis- 
eases, the  fluid  portion  of  the  blood  may  contain  innumerable 
organisms,  and  destruction  of  the  blood  cells  occurs. 

In  inflammation  of  tissue  the  circulation  of  the  blood  in 
the  inflamed  part  undergoes  certain  characteristic  changes.  At 
the  beginning  there  is  an  increase  in  the  blood  going  to  the  part. 
This  is  followed  by  a  slowing  of  the  blood  stream  in  the  small 
vessels,  and  the  collecting  of  the  blood  cells  in  the  capillaries 
and  veins.  These  circulatory  changes  are  followed  by  the  migTa- 
tion  of  the  blood  cells,  and  the  escape  of  the  fluid  portion  of  the 
blood  into  the  surrounding  tissue.  The  character  of  the  above 
circulatory  changes  depends  on  the  extent  of  the  injury  to  the 
tissue. 

Palpitation. — This  disturbance  in  domestic  animals  seems  to 
be  purely  functional.  It  may  occur  independent  of  any  organic 
heart  disease.  A  highly  nervous  condition,  excitement,  over- 
exertion, debility  from  disease  and  the  feeding  of  an  improper 
ration  are  the  common  causes. 

The  heart  beats  are  so  violent  and  tumultuous  as  to  shake 
the  body,  and  be  noticed  when  standing  near  the  animal. 
The  heart  sounds  are  louder  than  normal  and  the  pulse  beats 
small  and  irregular.  It  may  be  differentiated  from  spasm  of 
the  diaphragm  by  determining  the  relationship  of  the  heart 
beats  to  the  alirupt  shocks  observed  in  the  costal  and  flank 
regions. 

The  treatment  consists  in  keeping  the  animal  quiet  and 
avoiding  any  excitement.  A  quiet  stall  away  from  the  other 
animals  is  best.     The  treatment  of  palpitation  resulting  from 


106  NON-SPECIFIC  OR  GENERAL  DISEASES 

some  organic  heart  disease  must  be  directed  largely  at  the 
original  disease.  Morphine  is  commonly  used  for  the  treat- 
ment of  this  disorder.  Weak,  ana?mic  animals  should  receive 
blood  and  bitter  tonics.  If  we  have  reason  to  believe  that  the 
disturbance  is  caused  by  improper  feeding,  the  animal  should 
receive  a  spare  diet  for  a  few  days.  In  such  cases  it  is  advis- 
able to  administer  a  physic. 

Pericarditis. — Inflammation  of  the  pericardial  sack  is 
usually  a  secondary  disease.  It  is  frequently  met  with  in  in- 
fluenza, contagious  pleuropneumonia,  hog-cholera  and  rheuma- 
tism. Cattle  may  suffer  from  traumatic  pericarditis  caused  by 
sharp,  pointed,  foreign  bodies  passing  through  the  wall  of  the 
reticulum  and  penetrating  the  pericardial  sack.  The  jagged 
ends  of  fractured  ribs  may  cause  extensive  injury  to  neighbor- 
ing parts,  and  the  inflammation  spreads  to  the  pericardial  sack. 

The  symptoms  of  pericarditis  may  not  be  recognized  at  the 
very  beginning  when  the  disease  occurs  as  a  complication  of 
influenza,  or  infectious  pleuropneumonia.  The  manifestation 
of  pain  by  moving  about  in  the  stall,  refusing  to  eat  and  the 
anxious  expression  of  the  face  are  the  first  symptoms  that  the 
attendant  may  notice.  The  body  temperature  is  higher  than 
normal,  and  the  pulse  rapid  and  irregular.  On  auscultation, 
friction  sounds  that  correspond  to  the  tumultuous  beats  of  the 
heart  are  heard.  When  fluid  collects  within  the  pericardial 
sack,  the  heart  beats  become  feeble  and  tlie  pulse  weak.  Labored 
breathing  and  bluish  discoloration  of  the  lips  follow.  The 
disease  usually  runs  a  very  acute  course.  The  prognosis  is 
unfavorable. 

The  treatment  recommended  in  pneumonia  is  indicated 
in  this  disease.  Absolute  rest  and  the  feeding  of  an  easily 
digested,  laxative  diet  is  a  very  essential  part  of  the  treatment. 
At  the  very  beginning  morphine  may  be  given  to  quiet  the 
tumultuous  beats  of  the  heart.  Cold  applications  to  the  chest 
wall  in  the  form  of  ice  packs  should  be  used.     Heart  tonics  and 


DISEASES  OF  THE  CIRCULATORY  ORGANS 


107 


stimulants  such  as  digitalis,  strychnine  and  alcohol  should  be 
administered  when  the  pulse  beats  weaken.  To  promote  absorp- 
tion of  the  exudate,  iodide  of  sodium  may  be  given.  ]\[ustard 
paste,  or  a  cantharides  blister  applied  over  the  region  of  the 
heart  is  useful  in  easing  the  pain  and  overcoming  the  in- 
flammation. If  fluid  collects  in  sufficient  quantity  to  seriously 
interfere  with  the  heart  action,  the  sack  may  be  punctured  with 


Fig.   24. — Elephantiasis  in  horse. 

the  trocar  and  cannula  and  the  fluid  withdrawn.  Great  care 
must  be  used  to  avoid  injury  to  the  heart  and  infection  of  the 
part. 

Acute  Lymphangitis. — This  is  an  inflammation  of  the 
lymphatic  vessels  of  one  or  both  hind  limbs.  The  attack  comes 
on  suddenly  and  usually  occurs  in  connection  with  rest,  and  in 
horses  that  are  of  slow,  quiet  temperament.  The  exciiing 
cause  is  an  infection  of  the  part  with  bacteria,  the  infection 


108  NOx\-SPECIFIC  OR  GENERAL  DISEASES 

probably  occurring  through  some  abrasion  or  small  wound  in 
the  skin. 

The  local  symptoms  are  swelling,  tenderness  and  lameness 
in  the  affected  limb.  The  animal  may  refuse  to  support  its 
weight  on  the  atlected  limb.  The  lymphatic  glands  in  the  region 
are  swollen,  and  the  swelling  of  the  limb  pits  on  pressure.  In 
the  chronic  form  of  the  disease,  the  regions  of  the  cannon  and 
foot  remain  permanently  enlarged,  and  the  swelling  is  more 
firm  than  it  is  in  the  acute  fonn  (Fig.  24). 

The  general  symptoms  are  high  body  temperature,  rapid 
pulse  and  the  partial  or  complete  loss  of  appetite. 

The  following  treatment  is  recommended:  Exercise  is  indi- 
cated in  cases  that  are  not  sufficiently  advanced  to  cause  severe 
lameness,  or  inability  to  use  the  limb;  rest  and  the  application 
of  woollen  bandages  wrung  out  of  a  hot  water  solution  of  liquor 
cresolis  compound  are  recommended;  Epsom  salts  in  one-half 
pound  doses  may  be  given  and  repeated  in  two  or  three  days ;  a 
very  light  diet  of  soft  feed  should  be  given;  liniments  should 
not  be  applied  until  the  soreness  in  the  limb  has  subsided; 
iodide  of  potassium  may  be  given  twice  daily  with  the  feed. 

QUESTIONS 

1.  What  are  the  functions  of  the  blood  and  lymph? 

2.  State  the  changes  occurring  in  the  circulation  in   inflamed  tissue. 

3.  What  is  palpitation?     Give  the  causes  and  treatment. 

4.  What  are  tlie  common  causes  of  pericarditis? 

5.  Give  the  causes  and  treatment  of  acute  lymphangitis. 


CHAPTER  X 
DISEASES  OF  THE  NERVOUS  SYSTEM 

General  Discussion. — The  nervous  system  mav  be  divided 
into  central  and  peripheral  portions.  The  central  portion  com- 
prises the  brain  or  encephalon  and  the  spinal  cord.  These 
organs  are  lodged  in  the  cranial  cavity  and  spinal  canal.  The 
nerves  and  ganglia  comprise  the  peripheral  portion.  The  nerves 
form  white  cords  that  are  made  up  of  nerve  fibres.  The  ganglia 
are  grayish  enlargements  formed  by  nerve  cells  and  supporting 
tissue,  situated  at  the  origin  of  the  nerve  trunk  or  along  its  course. 

The  brain  is  an  oval  mass  of  nerve  tissue  elongated  from 
before  to  behind,  and  slightly  depressed  from  above  to  below. 
It  terminates  posteriorly  in  the  spinal  cord.  It  is  divided  into 
three  portions:  cerebrum,  isthmus  and  cerebellum  (Fig.  25). 

The  cerebrum  forms  the  anterior  portion.  It  is  divided  into 
two  lateral  lobes  or  hemispheres  by  a  deep  longitudinal  fissure. 
The  surface  of  the  cerebral  hemispheres  is  gray  and  roughened  by 
pleats  or  folds  separated  by  grooves  or  fissures.  The  gray  or 
cortical  layer  is  distinct  from  the  white  or  connecting  structure. 
The  cortical  layer  is  made  up  of  nerve  cells  or  areas  which  con- 
trol the  voluntary  muscles  of  the  body.  It  is  connected  with  the 
special  senses  of  touch,  temperature  and  muscle-sense.  The 
gray  layer  is  connected  with  the  posterior  portion  of  the  brain, 
the  isthmus  or  medulla  oblongata,  by  the  white  nerve  tissue. 

The  isthmus  or  medulla  oblongata  is  elongated  from  before 
to  behind  and  connects  the  cerebral  hemispheres  with  the  spinal 
cord,  anteriorly  and  posteriorly.  It  is  divided  into  several 
different  portions,  and  is  made  up  largely  of  white  connecting 
fibres  with  nuclei  of  gray  matter  scattered  through  them.  The 
isthmus  is  hollowed  out  by  a  system  of  small  ventricles  that 
extend  from  the  cerebral  hemispheres  to  the  spinal  cord,  where 

109 


110 


NON-SPECIFIC  OR  GENERAL  DISEASES 


they  terminate  in  a  small,  central  canal.  The  isthmus  is  the 
highway  between  the  spinal  cord  and  the  higher  nerve  centres. 
It  has  in  it  certain  cell  centres  that  give  origin  to  six  of  the 
cranial  nerves. 

The  third  division  of  the  brain  is  the  cerehellum.  This  is  a 
single  mass  supported  by  the  isthmus.  It  is  situated  posterior 
to  the  cerebrum,  from  which  it  is  separated  by  a  transverse  fold 


Fio.   25. — Photograph  of    model    of    horse's    brain  :  (D)    longitudinal   section;    (E)  lateral 
view;  (A)  cerebrum;  (B)  cerebellum;  and  (C)  isthmus. 

of  the  membranes  covering  the  brain.  This  mass  of  nerve  tissue 
is  much  smaller  than  the  cerebrum.  The  white  neiwe  tissue 
forms  central  nuclei  which  send  out  branches  that  ramify  in  every 
direction.  The  centre  of  the  muscular  sense  is  said  to  be  located 
in  this  division  of  the  brain.  A  second  function  is  the  mainten- 
ance of  body  equilibrium  through  its  connection  with  the  nerve 
of  the  middle  ear. 

The  spinal  cord  commences  at  the  posterior  opening  (occipi- 


DISEASES  OF  THE  NERVOUS  SYSTEM  111 

tal  foramen)  of  the  cranial  cavitv,  and  terminates  posteriorly  in 
the  lumbar  region  at  the  upper  third  of  that  portion  of  the  spinal 
canal  belonging  to  the  sacrum.  It  is  thick,  white  in  color,  irregu- 
larly cylindrical  in  shape,  slightly  flattened  above  and  below  and 
reaches  its  largest  diameter  in  the  lower  cervical  and  lumbar 
regions.  The  spinal  canal  is  lined  by  the  outer  membrane  that 
envelops  the  cord,  which  aids  in  fixing  this  organ  to  the  wall  of 
the  canal.  The  spinal  cord  is  formed  by  white  and  gray  nerve 
tissue.  The  gray  tissue  is  situated  within  the  w4iite,  and  it  is 
arranged  in  the  form  of  two  lateral  comma-shaped  columns  con- 
nected by  a  narrow  commissure  of  gray  matter.  The  extremities 
of  the  lateral  gray  columns  mark  the  origin  of  the  superior  and 
inferior  roots  of  the  spinal  nerves.  The  white  tissue  of  the  cord 
is  also  divided  into  lateral  portions  by  superior  and  median  fis- 
sures. The  inferior  fissure  does  not  extend  as  far  as  the  gray 
commissure,  leaving  the  lateral  inferior  columns  connected  by  a 
white  commissure.  There  are  certain  centres  in  the  spinal  cord 
that  are  capable  of  carrying  on  certain  reflex  actions  independent 
of  the  chief  centre  in  the  brain.  The  white  matter  of  the  cord 
is  made  up  of  paths  over  which  impulses  to  and  from  the  brain 
are  transmitted. 

There  are  tivelve  pairs  of  cranial  nerves.  Two  pairs  belong 
exclusively  to  the  special  senses,  smell  and  sight.  Altogether 
there  are  ten  pairs  that  are  devoted  to  functions  connected  wnth 
the  head,  either  as  nerves  of  the  special  senses  or  in  a  motor  or 
sensory  capacity  (Figs.  26  and  27).  There  are  two  pairs  dis- 
tributed to  other  regions.  These  are  the  tenth  and  eleventh  pairs. 
The  tenth  pair  or  pneumogastric  is  distributed  to  the  vital  organs 
lodged  within  the  body  cavities. 

There  are  forty-two  or  forty-three  pairs  of  spinal  nerves  given 
off  from  the  spinal  cord.  The  spinal  nerves  have  two  roots, 
superior  and  inferior.  The  superior  is  the  sensory  root  and  the 
inferior  is  the  motor  root,  both  uniting  to  form  a  mixed  nerve 


112  NON-SPECIFIC  OR  GENERAL  DISEASES 

trinik.     The  sensory  root  possesses  a  ganglion  from  whicli  it 
originates. 

Generally  speaking,  the  cerebrospinal  system  deals  with  the 
special  senses,  movement  of  skeletal  or  voluntary  muscles  and 
cutaneous  and  muscular  sensations.  In  addition  to  the  above 
there  is  a  distinct  system  termed  the  sympathetic.  The  sympa- 
thetic system  consists  of  a  long  cord,  studded  with  ganglia,  ex- 
tending from  the  base  of  the  neck  to  the  sacrum.  The  ganglia 
are  connected  with  the  inferior  roots  of  the  spinal  nerves.     This 

Fia.  26.  Fig.  27. 


Fig.   26. — Unilateral  facial  paralysis  caused  by  injury  to  seventh  cranial  nerve;  note  position 

of  lip. 
Fig.  27. — Bilateral  facial  paralysis.     This  colt  was  affected  with  facial  paralysis  when  born. 

cord  is  connected  with  groups  of  ganglia  and  nerve  fibres  in  the 
abdominal  region,  and  this  in  turn  is  connected  with  terminal 
ganglia  in  distant  tissues.  This  system  of  nerves  is  distributed 
to  the  vital  organs  of  the  body. 

Congestion  and  Anaemia  of  the  Brain. — In  congestion  of  the 
brain,  the  blood-vessels  distributed  to  the  nerve  tissue  become 
engorged  with  blood.    It  may  be  either  active  or  passive. 

The  cause  of  ancvmia  of  the  brain  is  an  insufficient  blood 
supply.  This  may  be  due  to  an  abundant  hemorrhage  and  car- 
diac weakness  caused  by  shock  or  organic  heart  disease. 


DISEASES  OF  THE  NERVOUS  SYSTEM  113 

The  causes  of  congestion  of  the  brain  are  faulty  methods  of 
care  and  feeding.  It  sometimes  occurs  when  horses  are  shipped 
in  poorly  ventilated  cars,  or  kept  in  close  stables.  Climatic 
changes,  or  changing  the  stable  and  feed,  may  cause  it.  Ex- 
tremely fat  animals  and  animals  that  are  rapidly  putting  on  fat 
are  predisposed  to  this  disorder.  Improper  methods  of  feeding, 
lack  of  exercise,  constipation  and  excitement  are  the  most  com- 
mon causes.  Passive  congestion  may  result  from  pressure  on 
the  jugular  vein  by  obstructing  the  flow  of  blood  from  the  brain, 
and  raising  blood  pressure  in  the  blood-vessels  of  the  brain.  It 
is  sometimes  caused  by  organic  heart  trouble. 

The  symptoms  come  on  very  suddenly  in  congestion  of  the 
brain.  The  disease  may  manifest  itself  as  soon  as  the  animal 
is  moved  out  of  the  stall  or  bed,  or  it  may  come  on  while  it  is 
feeding.  In  slight  cases,  the  animal  appears  excited  and  rest- 
less, the  eyes  are  bright,  the  pupils  are  dilated,  and  the  pulse 
beats  and  respirations  quickened.  If  the  animal  is  moving 
about,  it  may  stop  suddenly  and  show  marked  symptoms  of  a 
nervous  disorder,  such  as  turning  around,  running  straight  ahead 
and  falling  down.  The  period  of  excitement  is  usually  brief  and 
may  be  followed  by  marked  depression.  The  mucous  membranes 
of  the  head  are  a  deep,  red  color. 

The  symptoms  in  amx-mic  conditions  of  the  brain  are  loss  of 
consciousness,  stumbling,  falling  to  the  ground  and  sometimes 
convulsions.  The  pig  and  dog  may  vomit.  Favorable  cases 
return  to  the  normal  within  a  few  hours.  Acute  inflammatory 
diseases  of  the  brain  and  its  coverings  are  associated  with  cere- 
bral hypera?mia  or  congestion. 

The  treatment  of  mild  cases  is  to  give  the  animal  quiet, 
well-ventilated  quarters,  where  it  can  not  injure  itself.  The 
animal  should  be  first  subjected  to  a  severe  diet  and  later  given 
easily-digested  feed.  If  it  appears  greatly  excited,  bleeding 
should  be  practised.  Cold  applications  to  the  head  should  be 
used  in  all  cases  in  the  small  animals.  For  internal  treatment, 
8 


114  NON-SPECIFIC  OR  GENERAL  DISEASES 

purgatives  are  indicated.  In  cases  of  ana?mia,  stimulants,  vigoi.*- 
ous  massage,  artificial  respiration  and  injection  of  physiological 
salt  solution  are  indicated. 

Sunstroke  and  Heatstroke. — Most  writers  make  no  distinc- 
tion between  heatstroke  and  sunstroke.  The  latter  is  caused  by 
the  direct  rays  of  the  sun  falling  on  the  animal,  and  the  former 
from  a  high  temperature  and  poor  circulation  of  air  in  the  sur- 
roundings. Under  such  conditions,  the  physical  condition  of 
the  animal  and  exertion  play  an  important  part  in  the  production 
of  the  nervous  disturbance. 

The  first  symptoms  usually  noted  are  rapid,  labored  breath- 
ing, depression  and  an  anxious  expression  on  the  face.  The 
horse  usually  stops  sweating.  The  body  temperature  is  extremely 
high,  the  pulse  beats  weak,  the  animal  trembles,  falls  to  the 
ground  and  dies  in  a  convulsion.  Unless  measures  directed 
toward  relief  of  the  animal  are  taken  early  in  the  attack,  death 
commonly  occurs.  Overheating  is  rather  common  in  horses  that 
are  worked  hard  during  the  extremely  warm  weather.  Horses 
that  have  been  once  overheated  are  afterwards  unable  to  stand 
severe  work  during  the  hot  months  of  the  year.  Horses  in  this 
condition  become  unthrifty,  do  not  sweat  freely  and  pant  if  the 
work  is  hard  and  the  weather  is  warm. 

The  preventive  measures  consist  in  not  exposing  animals  that 
are  fat,  or  out  of  condition  to  severe  exercise  if  the  day  is  close 
and  hot,  especially  if  they  are  not  accustomed  to  it.  \Vhen  hand- 
ling or  working  animals  during  hot  weather  all  possible  precau- 
tions to  prevent  overheating  should  be  practised. 

The  treatment  consists  in  placing  the  animal  in  a  cool,  shady 
place  and  fomenting  the  body  with  cold  water.  The  cold  packs 
or  cold  fomentations  should  be  applied  to  the  head  and  forepart 
of  the  body  only.     Small  doses  of  stimulants  may  be  given. 

Meningo-cerebritis. — The  discussion  of  inflammation  of  the 
brain  and  its  coverings  can  be  combined  conveniently,  as  the 
causes,  symptoms  and  treatment  vary  but  little.    This  disorder  ia 


DISEASES  OF  THE  NERVOUS  SYSTEM  115 

met  with  in  all  species  of  domestic  animals,  but  it  is  most  com- 
mon in  horses  and  mules.  Some  writers  state  that  meningo- 
cerebritis  is  more  common  during  the  warm  season  than  it  is 
in  the  winter.  However,  this  does  not  hold  true  in  all  sections. 
In  the  middle  west,  this  disease  is  more  common  in  late  fall  and 
winter. 

It  is  commonly  caused  by  taking  into  the  body  with  the  feed 
and  water  certain  organisms  and  toxins  that  are  capable  of  pro- 
ducing an  inflammation  of  the  brain.  The  infectious  organism 
or  toxins  are  taken  up  by  the  absorbing  vessels  of  the  intestines. 

The  secondary  form  of  the  disease  usually  occurs  in  connec- 
tion with  other  diseases  such  as  influenza,  tuberculosis  and  acute 
pharyngitis,  or  as  a  result  of  wound  infection.  Unhygienic  con- 
ditions, as  unsanitary  and  poorly  ventilated  stables  and  filthy 
drinking  places,  play  a  very  important  part  in  the  production 
of  the  simple  or  acute  form  of  meningitis. 

Sudden  changes  in  the  feed  and  the  feeding  of  rotten,  mouldy 
feeds  may  cause  it.  In  the  fall  and  winter  it  may  follow  the 
feeding  of  too  heavy  a  ration  of  shredded  fodder  or  any  other 
dry  feed.  Other  exciting  causes  are  overexertion,  changes  in 
climate,  excitement,  injuries  to  the  head  and  the  feeding  of  too 
heavy  and  concentrated  a  ration. 

The  symptoms  vary  in  the  different  individuals,  but  in  gen- 
eral they  are  the  same.  At  first  the  animal  is  dull,  or  extremely 
nervous  and  sensitive  to  sounds.  The  pupils  of  the  eye  are  un- 
evenly contracted  at  first,  later  dilated.  The  eyes  may  appear 
staring,  or  they  are  rolled  about,  so  that  the  white  portion  is 
prominent.  The  unusual  excitement  is  manifested  in  different 
ways  by  the  different  species.  During  the  dull  period  the  animal 
is  indifferent  to  its  surroundings.  AMien  it  is  excited,  the  pulse 
beats  and  respirations  are  accelerated.  The  body  temperature  is 
often  elevated  early  in  the  disease.  There  is  a  partial  or  com- 
plete loss  of  appetite.  Paralysis  may  be  the  most  prominent 
s}Tnptom.     The  animal  lies  in  a  natural  position,  or  stretched 


116  NON-SPECIFIC  OR  GENERAL  DISEASES 

out  and  lifting  the  head  occasionally  and  moving  the  limbs,  but 
it  is  unable  to  rise.  Loss  of  sensibility  may  gradually  progress 
until  the  animal  becomes  semiconscious,  or  comatose. 

In  case  the  inflammation  is  acute  and  involves  the  greater 
portion  of  the  brain  and  its  coverings,  death  occurs  within  a  few 
days.  Occasionally  the  animal  survives  several  weeks.  There 
are  few  permanent  or  complete  recoveries. 

The  principal  lines  of  treatment  are  preventive  measures"  and 
careful  nursing.  This  is  one  of  the  diseases  that  can  be  largely 
prevented  by  observing  all  possible  sanitary  precautions  in  car- 
ins  for  animals.  It  is  admitted  bv  writers  that  the  greater 
majority  of  cases  of  inflammation  of  the  brain  and  its  coverings 
are  caused  by  infection.  Proper  stable  construction,  ventilation 
and  disposal  of  the  manure,  an  occasional  disinfection  of  the 
stable,  cleaning  and  disinfecting  the  drinking  places  and  water 
tanks,  and  the  necessary  attention  to  the  ration  greatly  reduce 
the  loss  from  this  disease. 

The  animal  should  be  gotten  into  a  dark,  quiet,  roomy  stall 
that  is  well  bedded.  A  swing  may  be  placed  under  a  large  animal 
if  it  is  able  to  support  any  of  its  weight,  and  there  is  no  evidence 
of  nervous  excitement.  We  should  do  nothing  to  disturb  it.  If 
possible,  the  position  of  the  animal  that  is  unable  to  get  up  should 
be  changed,  and  the  bed  kept  clean  and  dry.  Cold  in  the  form  of 
wet  or  ice  packs  should  be  applied  to  the  head  during  the  acute 
stage.  Symptoms  of  excitement  must  be  overcome  by  large  doses 
of  sedatives.  Iodide  of  potassium  and  strychnine  may  help  in 
overcoming  the  paralysis.  The  bowels  should  be  emptied  by 
giving  an  occasional  physic.  A  very  light,  easily  digested  diet 
should  be  fed. 

Partial  or  Complete  Paralysis  of  the  Posterior  Portion  of 
the  Body. — This  disorder  is  especially  common  in  the  small 
animals.     The  hog  is  most  frequently  affected. 

The  following  causes  may  be  mentioned:  Inflammation  of 
the  spinal  cord  commonly  occurs  in  influenza,  strangles  and 


DISEASES  OF  THE  NERVOUS  SYSTEM  117 

mixed  infectious;  constipation  brought  on  by  improper  feed- 
ing and  insufficient  exercise  is  a  predisposing  cause;  injuries 
such  as  strains  and  blows  in  the  region  of  the  back  may  also  cause 
it ;  compression  of  the  spinal  cord  by  the  vertebmp  is  no  doubt  a 
very  connnon  cause ;  dislocation,  enlargement  of  the  disks  between 
the  vertebra",  bony  enlargements  resulting  from  strains  and  in- 
juries, rickets,  tuberculosis  and  actinomycosis  and  tumors  com- 
monly cause  compression  of  the  cord.  It  is  rarely  caused  by 
parasites.  Young,  fat  animals  are  especially  prone  to  injuries 
in  the  region  of  the  back.  Such  animals  may  suffer  from  mal- 
nutrition of  the  bones,  and  complete  fractures  of  the  thigh  bones 
may  occur.  Extreme  heat  from  the  sun's  rays  and  close,  hot 
quarters  are  probable  causes. 

The  symptom  that  is  most  prominent  is  the  partial  or  com- 
plete loss  of  control  over  the  movements  of  the  hind  parts.  The 
appetite  may  be  little  interfered  with.  The  animal  may  sit  on 
the  haunches,  with  the  limbs  projecting  forward,  or  swing  the 
hind  quarters  from  side  to  side  in  walking  or  trotting.  Irregu- 
larity in  the  animal's  movements  is  especially  noticeable  when 
turning  or  backing.  In  case  the  animal  suffers  pain,  the  spine 
is  held  rigid  or  arched,  and  when  forced  to  move,  marked  evi- 
dence of  pain  occurs.  There  may  be  a  decrease  or  increase  in  the 
sensibility  of  the  part.  The  increase  in  sensibility  is  noticed  on 
striking  the  muscles  with  the  hand  or  rubbing  the  hair  the  wrong 
way.  Spasmodic  twitching  or  contractions  in  the  muscles  some- 
times occur.  There  is  frequent  elevation  of  temperature.  The 
animal  is  unable  to  pass  urine  or  fa?ces,  or  there  may  be  an 
involuntary  passage  of  the  body  excretions. 

The  outcome  of  this  disease  is  unfavorable.  Acute  inflam- 
mation of  the  covering  of  the  cord  may  subside  within  a  few  days. 
Cases  that  do  not  recover  within  a  few  weeks  should  be  destroyed. 
Paralysis  of  the  hind  parts  should  not  be  confused  with  rheuma- 
tism, azoturia  and  other  disorders  that  may  interfere  with  the 
movements  of  the  posterior  portion  of  the  body. 


118  NON-SPECIFIC  OR  GENERAL  DISEASES 

The  treatment  is  largely  along  preventive  lines.  A  predis- 
position toward  rickets,  and  injuries,  may  be  prevented  by  feed- 
ing a  proper  ration,  and  permitting  the  animal  to  take  exercise. 
The  quarters  and  the  attendant  are  frequently  responsible  for 
injuries.  If  this  is  the  case,  the  rough  handling  of  the  animals 
should  be  immediately  corrected,  and  any  condition  of  the  quar- 
ters that  favors  the  crowding  or  piling  up  of  animals  should  be 
changed.  Large  animals  may  be  placed  in  swings  if  they  are 
able  to  support  a  part  of  their  weight  on  the  hind  limbs.  This  is 
especially  indicated  at  the  very  beginning  of  the  disorder.  Small 
animals  should  be  given  a  good  bed.  A  very  light,  easily  digested 
ration  should  be  fed.  An  occasional  physic  should  be  adminis- 
tered. Strychnine  and  iodide  of  potassium  may  be  given.  Cold 
applications  to  the  back  are  indicated. 

QUESTIONS 

1.  What    organs    comprise    the    central    portion    of    the    nervous    system? 

Peripheral  portion? 

2.  Give  a  general  description  of  the  brain. 

3.  Give  a  general  description  of  the  spinal  cord. 

4.  What  is  the  sympathetic  system? 

5.  Describe  the  causes  and  symptoms  of  congestion  of  the  brain. 

6.  What  is  heatstroke?     Give  the  treatment. 

7.  Give  the  preventive  and  curative  treatment  of  inflammation  of  the  brain. 

8.  State  the  causes,  and  give  the  proper  treatment  of  paralysis  of  the  pos- 

terior portion  of  the  body. 


CHAPTER  XI 
DISEASES  OF  THE  SKIN 

General  Discussion. — The  two  layers  that  form  the  skin  are 
the  epidermis  and  the  derma.  The  cells  of  the  enter  layer  or  epi- 
dermis are  of  two  kinds.  The  snperficial  portion  is  formed  by 
horny,  flattened  cells  and  the  deeper  by  softer  cells.  This  layer 
of  the  skin  varies  greatly  in  thickness  in  the  different  species. 
The  derma  is  composed  of  some  mnscnlar  fibres  interwoven  with 
the  connective-tissne  fibres.  It  contains  the  roots  of  the  hair  fol- 
licles, sweat  and  oil  glands.  The  external  face  which  is  covered 
by  the  epidermis  shows  a  mnltitnde  of  little  elevations.  These 
are  the  vascnlar  and  nervons  papilla.  In  addition,  it  shows 
openings  through  which  the  hairs  and  the  skin  glands  pass. 
The  inner  surface  is  united  more  or  less  closely  to  the  muscular 
or  underlying  tissue  by  a  layer  of  fibro-fatty  tissue. 

The  appendages  of  the  shin  are  the  hairs  and  horny  produc- 
tions. The  horny  productions  comprise  the  horns,  chestnuts, 
ergots,  claws  and  hoofs. 

The  hair  varies  in  length,  thickness  and  coarseness  in  the 
different  species,  and  the  different  regions  of  the  body.  In  addi- 
tion, breeding,  care,  heat  and  cold  may  cause  marked  variations 
in  the  thickness  of  the  coat.  Exposure  to  cold  causes  the  coat 
to  thicken.  High  temperatures  cause  the  short  hairs  to  drop 
out  and  the  coat  to  become  thin. 

Diseases  of  the  skin  may  be  classified  as  parasitic  and  non- 
parasitic. Parasitic  skin  diseases  are  caused  by  animal  and 
vegetable  parasites.  ISTon-parasitic  skin  diseases  are  caused  by 
irritation  to  the  skin  and  internal  causes.  Irritation  to  the  skin 
may  be  either  chemical,  thermic  or  mechanical.  The  internal 
causes  may  be  due  to  an  individual  predisposition  together  with 
digestive  disturbances  and  the  eating  of  feeds  too  rich  in  protein. 

119 


120  NON-SPECIFIC  OR  GENERAL  DISEASES 

In  this  chapter  parasitic  skin  diseases  produced  by  insects  will 
not  be  discussed. 

Falling  Out  of  the  Hair  and  Feathers. — Falling  out  of  the 
hair  and  feathers  frequently  occurs  independent  of  parasitic 
diseases.  This  condition  does  not  occur  as  an  independent  dis- 
order, but  as  a  secondary  affection.  It  is  due  to  faulty  nutrition, 
and  irritation  to  the  skin.  Intestinal  diseases,  insufficient  feed 
and  feed  of  bad  quality  are  common  causes.  Animals  that  are 
fed  a  heavy  ration,  or  that  lie  on  dirty,  wet  bedding  frequently 
lose  large  patches  of  hair.  Sheep  that  are  dipped  in  late  fall 
and  early  winter,  or  exposed  to  wet,  cold  weather  may  lose 
a  i)art  of  their  fleece.  It  is  not  uncommon  for  animals  toward 
the  latter  period  of  pregnancy,  or  that  sweat  freely,  to  lose  patches 
of  hair. 

Falling  out  of  the  hair  heals  of  itself  within  a  few  weeks. 

The  'preventive  measures  are  of  special  importance  in  sheep 
and  horses.  This  consists  in  avoiding  conditions  that  may  lead 
to  alopecia  and  in  correcting  the  diet.  In  horses  the  regions  of 
the  mane  and  tail  should  be  washed  with  soap,  or  rubbed  with 
alcohol  and  spirits  of  camphor,  equal  parts.  Treatment  should 
be  persisted  in  for  a  long  period  if  necessary. 

Urticaria,  "  Nettlerash." — Urticaria  is  characterized  by 
roundish  elevations  that  appear  quickly  and  become  scattered 
over  a  part  or  the  whole  surface  of  the  skin.  They  are  caused 
by  an  inflammatory  infiltration  of  the  deeper  layers  of  the  skin. 
Horses  and  hogs  are  most  frequently  affected. 

The  causes  of  urticaria  are  irritating  juices  of  certain  plants, 
secretions  of  flies,  ants  and  some  caterpillars,  irritating  drugs, 
scratching,  sweating  and  the  action  of  cold  on  a  warm  skin.  It 
has  been  observed  in  connection  with  the  feeding  of  certain  legii- 
minous  feeds  and  digestive  disturbances.  Horses  that  are  fat,  or 
putting  on  flesh  rapidly,  seem  to  be  predisposed  to  this  disorder. 
Urticaria  may  occur  in  certain  infectious  diseases. 

The  characteristic  symptom  is  the  formation  on  the  skin  of 


DISEASES  OF  THE  SKIN  121 

roundish  elevations  or  ''  hives.''  There  may  be  an  elevation  of 
body  temperature  and  partial  loss  of  appetite.  Small  animals 
may  act  restless  and  show  evidence  of  itching  or  pain.  This 
spnptom  is  very  common  in  hogs.  The  eruption  may  last  only 
a  few  hours  or  a  few  days,  or,  because  of  the  animal's  scratching 
or  rubbing  the  part,  the  skin  may  become  scabby  and  small 
pustules  form. 

An  important  preventive  measure  is  to  avoid  the  use  of  agents 
capable  of  irritating  the  skin  and  producing  urticaria  when  treat- 
ing parasitic  skin  diseases.  It  is  very  advisable  to  give  the  animal 
a  saline  cathartic  (Epsom  or  Glauber's  salts).  The  skin  may 
be  washed  with  cold  water,  or  a  weak  water  solution  of  perman- 
ganate of  potassium. 

Acne,  "  Summer  Rash." — In  this  skin  disease  the  oil  glands 
and  hair  follicles  are  inflamed  and  sometimes  infected  with  pus 
germs.  This  results  in  skin  eruptions  varying  in  size  from  the 
point  of  a  pin  to  about  a  quarter  of  an  inch  in  diameter.  This 
inflammation  is  most  prominent  during  the  warm  weather. 

The  causes  are  local  irritation  to  the  skin  from  lying  on 
filthy  floors,  sweating  and  irritation  from  the  harness.  According 
to  some  writers,  pus  germs  are  the  only  cause,  the  mechanical 
agents  merely  aiding  in  the  production  of  the  infection. 

The  face,  side  of  the  neck,  shoulders,  back  and  sides  of  the 
trunk  and  quarters  are  the  usual  seats  of  disease.  The  pimples 
or  nodules  may  disappear  within  a  few  weeks,  or  persist  through- 
out the  warm  season.  The  eruption  may  disappear  without  leav- 
ing scars,  or  suppuration  occurs  and  small  bald  spots  result. 

The  treatment  consists  in  removing  the  cause  of  the  disease 
and  cleaning  the  skin  with  antiseptic  Avashes.  The  surroundings 
of  the  animal  must  be  kept  clean  and  a  good  bed  provided.  If 
possible,  the  horse  should  be  laid  oft'  from  work  as  soon  as  the 
condition  is  noted.  Washing  the  part  with  a  weak  water  solution 
of  permanganate  of  potassium  may  be  practised  daily.  Fowler's 
solution  of  arsenic  may  be  given.  This  may  be  given  with  the 
feed. 


122  NON-SPECIFIC  OR  GENERAL  DISEASES 

Eczema. — This  is  an  inflammation  of  the  vascular  capilkry 
bodies  and  the  superficial  layer  of  the  skin.  There  may  be 
marked  inflammatory  exudate,  causing  the  surface  of  the  skin 
to  become  excessively  moist  and  more  or  less  itching.  Redness, 
vesicles  and  pustules  may  characterize  the  inflammation.  In  the 
chronic  form  the  skin  may  become  thickened  and  greatly  changed 
in  structure. 

Eczematous  inflammation  of  the  skin  may  occur  in  all  domes- 
tic animals,  but  it  is  most  common  in  the  dog.  In  the  horse 
local  eczema  (scratches)  is  common. 

The  most  frequent  cause  is  external  irritation.  Aceimau- 
lations  of  filth  on  the  skin  and  continual  wetting  of  the  part  are 
common  causes.  Mechanical  causes  are  rubbing,  pressure,  the 
action  of  the  sun's  rays  and  chemical  irritants.  Internal  causes, 
such  as  catarrhal  diseases  of  the  stomach  and  weakness  and 
emaciation  from  disease,  may  act  as  direct  or  predisposing  causes. 
Tender-skinned  animals  seem  to  be  predisposed  to  the  disease. 

The  symptoms  vary  in  the  different  species  of  animals.  In 
the  horse  the  thin  skin  posterior  to  the  fetlock  and  knee,  in  front 
of  the  hock  and  on  the  under  side  of  the  body  is  most  commonly 
inflamed.  Moisture  and  dirt  seem  to  be  the  most  common  causes. 
Eczema  may  involve  the  skin  covered  by  the  mane  and  tail  in 
animals  that  are  not  properly  groomed  and  inclined  to  rub  or 
scratch.  Cattle  may  suffer  from  eczematous  inflammations  in 
the  region  of  the  forehead,  back  of  neck  and  base  of  tail.  A  very 
common  form  of  the  disease  involves  the  space  between  the  toes. 
Sheep  freciuently  suffer  from  inflanniiation  of  the  skin  over  the 
fetlock  region.  The  skin  of  animals  having  long  fleeces,  or  heavy 
coats  of  hair  that  become  wet  at  a  time  when  there  is  no  oppor- 
tunity to  dry  out  quickly,  may  become  inflamed.  Dogs  are 
commonly  affected  by  the  acute  and  chronic  forms  of  eczema. 
Eczema  of  swine  is  limited  mostly  to  young  hogs.  It  is  rather 
rare,  exce]iting  in  hogs  that  are  pasturing  on  certain  kinds  of 
clover  and  rape,  or  on  muck  lands. 


DISEASES  OF  THE  SKIN  123 

The  inflammation  is  accompanied  by  a  marked  tenderness 
and  itching",  and  the  animal  licks  and  scratches  the  part.  This 
increases  the  e::tent  of  the  skin  lesions.  The  skin  appears  moist, 
later  dirty,  scabby  and  thickened.  Cracks  and  pustules  may 
form.     Gangrene  and  sloughing  of  the  skin  may  occur. 

The  treatment  is  both  preventive  and  curative.  Cases  of 
eczema  caused  by  filth  and  wetness  can  be  prevented  by  giving 
the  necessary  attention  to  keeping  the  skin  clean  and  not  allowing 
animals  access  to  muddy,  filthy  places.  Keeping  the  bed  clean 
and  regulating  the  diet  are  important  preventive  measures.  Be- 
fore the  inflammation  can  be  successfully  treated  the  cause  must 
be  removed. 

In  acute  eczema  it  is  advisable  to  protect  the  part  against 
water,  filth  and  air.  Powders  and  ointments  may  be  used  during 
the  early  stages  of  the  inflammation.  Two  parts  boric  acid, 
four  parts  flour,  and  one  part  tannic  acid  may  be  dusted  over 
the  moist  surface.  One  part  zinc  oxide  and  twelve  parts  vaseline 
is  a  useful  ointment.  Scratching  the  part  should  be  controlled 
in  every  case  by  muzzles,  collars  and  bandages.  Dirt  and  scales 
may  be  removed  from  the  skin  by  washing  with  cotton  soaked 
in  lime  water  or  linseed  oil.  The  animal  should  receive  laxative 
doses  of  Glauber's  salts  or  oil  every  few  days.  A  simple,  easily 
digested  ration  should  be  fed.  The  following  mixture  may  be 
applied  in  obstinate  cases :  oil  of  tar  and  soft  soap,  two  parts 
each,  and  alcohol  one  part. 

Common  Feed  Rashes. — This  title  includes  inflammation  of 
the  skin  caused  by  pasturing  on  buckwheat,  certain  clovers  and 
rape,  together  with  moisture  and  sunlight. 

Green,  flowering  buckwheat  is  more  dangerous  as  a  feed  for 
stock  than  is  the  grain  or  straw.  Clovers  and  rape  are  not  as 
dangerous  a  feed.  The  actual  cause  of  the  skin  becoming 
inflamed  is  not  known. 

The  skin  in  the  regions  of  the  face,  ears,  neck,  lower  surface 


121  NON-SPECIFIC  OR  GENERAL  DISEASES 

of  the  body  and  limbs  becomes  red  and  covered  with  vesicles. 
Later,  scabs  and  pus  may  form. 

The  treatment  consists  in  changing  the  ration  and  keeping 
the  animals  out  of  the  sun,  or  long  grass  and  weeds  for  a  few 
days.  This  is  all  the  treatment  required  in  most  cases.  It  may  be 
advisable  to  administer  a  physic.  If  pus  and  scabs  form,  the 
part  should  be  cleansed  daily  with  a  one  per  cent  water  solution 
of  permanganate  of  potassium. 

Herpes  (Fungous  Skin  Disease). — This  is  a  contagious 
disease  of  the  skin  caused  by  thread  fungi,  TricopJiyton  ton- 
surans and  epilans,  which  develop  in  the  skin  in  localized  areas, 
causing  vesicles,  scabs  or  scales  to  appear,  and  the  loss  of  the 
hair  over  the  part.  This  skin  disease  occurs  in  all  domestic 
animals,  but  it  is  most  commonly  met  with  in  cattle.  It  usually 
affects  young  cattle.  It  most  commonly  occurs  in  the  region  of 
the  face  and  neck.  Thick,  bran-like  crusts  form  over  the  scattered 
areas  of  the  skin  and  the  hair  drops  out  or  breaks  off.  The 
animals  frequently  rul)  the  infected  area. 

Prompt  treatment  may  prevent  the  spread  of  this  disease 
in  the  herd.  It  may  be  checked  by  quarantining  the  infected 
animals  and  scrubbing  the  stalls,  stanchions  and  walls  with  a 
disinfecting  solution.  Grooming  the  infected  animal  should  be 
discontinued.  This  skin  disease  responds  most  readily  to  oint- 
ments. Flowers  of  sulfur  one  part  and  lard  ten  parts  is  com- 
monly used  by  stockmen.  Sulfur-iodide  ointment,  or  tincture 
of  iodine  may  be  applied. 

QUESTIONS 

1.  Give  a  general  description  of  tlie  skin.  ♦ 

2.  Give  tlie  causes  and  treatment  of  falling  of  the  hair. 

3.  What  is  urticaria?     Give  tlie  treatment. 

4.  What  is  summer  rash?     Give  the  treatment. 
').  What  is  "  scratches  "?     Give  the  treatment. 
f>.  What  feeds  produce  rashes  of  the  skin? 

7.  What  fungus  produces  an  inflammation  of  the  skin  in  cattle?     Give  the 
treatment. 


CHAPTER  XII 
DISEASES  OF  THE  EYE 

General  Discussion. — The  eye  is  situated  in  the  orbital 
cavity,  to  which  it  is  attached  by  muscles  that  rotate  it  in  dif- 
ferent directions.  The  orbit  is  lined  by  fibro-fatty  tissues  that 
form  a  cushion  for  the  eye.  Anteriorly  it  is  protected  by  the 
eyelids,  and  in  birds  by  a  third  eyelid  that  corresponds  to  the 
membrana  nictitans  of  quadrupeds.  The  lachrymal  gland  which 
secretes  the  tears  keeps  the  above  parts  moist. 

The  eye  is  the  essential  organ  of  vision.  It  is  formed  by  a 
spherical  shell  which  encloses  fluid  or  semisolid  parts.  The 
shell  is  anteriorly  made  up  of  a  transparent  convex  membrane, 
the  cornea,  while  the  remainder  of  its  wall  is  formed  by  three 
opaque  layers  or  tunics. 

The  external  tunic  is  the  sclerotic.  It  is  a  white,  solid  mem- 
brane, forming  about  four-fifths  of  the  external  shell.  Its  ex- 
ternal face  is  related  to  the  muscles  and  fatty  cushion.  It 
receives  posteriorly,  a  little  lower  than  its  middle  portion,  the 
insertion  of  the  optic  nerve,  which  passes  through  the  shell  and 
spreads  out  to  form  a  very  thin  membrane,  the  retina  or  internal 
coat. 

The  retina  lines  about  two-thirds  of  the  posterior  portion  of 
the  shell  of  the  eye.  It  is  made  up  of  seven  layers.  The  essential 
layer  is  named  from  its  appearance,  rods  and  cones. 

The  paiddle  coat  is  the  choroid.  This  is  a  dark,  pigmented, 
vascular  and  muscular  membrane.  The  posterior  portion  is  in 
contact  with  the  retina.  Anteriorly  it  forms  the  ciliary  processes 
and  the  iris. 

The  media  of  the  eye  are  the  crystalline  lens,  vitreous  and 
aqueous  humors.  The  crystalline  lens  is  a  transparent,  biconvex 
body  sustained  by  the  ciliary  processes.     The  vitreous  humor  is 

125 


126  NON-SPECIFIC  OR  GENERAL  DISEASES 

a  transparent  jelly-like  substance  that  fills  all  the  cavity  of  the 
eye  posterior  to  the  lens.  The  aqueous  humor  is  a  liquid,  con- 
tained in  the  anterior  and  posterior  chambers  of  the  eye  in  front 
of  the  lens.  This  fluid  separates  the  iris  from  the  front  of  the 
lens. 

Examination  of  the  Eye. — In  examining  and  treating  the 
eye  we  should  avoid  rough  and  hasty  manipulation.  The  animal 
should  be  approached  slowly.  It  is  best  for  the  attendant  who  is 
familiar  with  the  animal  to  hold  it  for  the  examiner.  It  is 
advisable  on  approaching  the  animal  to  stroke  its  face,  and  in 
the  horse  to  brush  its  foretop  away.  The  hand  should  be  carried 
slowly  to  the  front  of  the  eye,  and  the  lids  separated  with  the 
fingers  and  thumb  if  we  wish  to  obtain  a  better  view  of  the  cornea. 
In  cattle  the  best  view  of  these  parts  can  be  obtained  by  taking 
hold  of  the  nose  and  lifting  the  head.  It  is  impossible  to  make 
a  satisfactory  examination  of  the  eye  outside  of  the  stable  Avhere 
the  light  is  coming  from  all  directions.  The  most  satisfactory 
conditions  under  which  a  general  examination  can  be  made  is 
to  stand  the  animal  facing  a  transom,  window  or  open  door.  We 
may  then  look  directly  into  the  eye  and  note  the  condition  of  the 
different  refracting  media. 

The  lens  should  appear  transparent  and  free  from  scars.  The 
aqueous  humor  free  from  any  cloudiness  or  precipitate.  Both 
pupillary  openings  should  be  the  same  size,  and  not  too  small 
or  too  large  in  the  bright  light.  As  we  look  through  the  pupil- 
lary openings,  both  the  lens  and  the  vitreous  humor  should  refract 
the  light  properly  and  not  appear  white  or  greenish-white  in 
color.  The  color  of  the  iris  should  be  noted.  If  it  lacks  lustre 
or  appears  dull,  this  may  indicate  an  inflammation.  In  periodic 
ophthalmia  in  horses  the  iris  loses  its  lustre  and  becomes  a  rusty- 
broAvm  color.  It  is  very  important  to  note  this  change  in  the 
appearance  of  the  iris.  We  should  note,  in  addition,  the  expres- 
sion of  the  animal's  face,  the  position  of  the  ears  and  eyelids  and 
manner  of  the  walk.    Horses  that  have  defective  sight  may  show 


DISEASES  OF  THE  EYE  127 

a  deep  wrinkle  in  the  upper  eyelid  when  startled  or  looking 
directly  at  an  object.  Animals  that  are  blind  hold  the  ears  in 
a  characteristic  position,  and  may  stumble  and  walk  over,  or  run 
into  objects  unless  stopped.  The  ophthalmoscope  is  a  very  useful 
instrument  for  determining  the  condition  of  the  different 
structures  of  the  eyes,  when  in  the  hands  of  persons  who  are 
trained  in  its  use. 

Conjunctivitis. — This  is  an  inflammation  of  the  mucous  mem- 
brane lining  the  eyelids  and  covering  the  eyeball.  The  two 
forms  of  conjunctivitis  common  in  domestic  animals  are  the 
catarrhal  and  purulent. 

The  symptoms  differ  in  the  two  forms  of  conjunctivitis. 
They  may  be  distinguished  from  each  other  by  the  difference 
in  the  character  of  the  inflammatory  discharge.  In  the  catarrhal 
form,  there  is  a  discharge  of  tears  and  the  lids  are  held  more  or 
less  closed.  The  mucous  membrane  is  usually  brick  red  in  color 
and  swollen.  A  little  later  the  discharge  becomes  heavier  and 
adheres  more  to  the  margins  of  the  lids.  The  lids  continue  ten- 
der and  the  inflammation  painful.  The  surface  of  the  cornea 
may  appear  white  and  the  blood-vessels  prominent,  but  it  is  only 
in  the  severe  cases  that  inflammation  of  this  portion  of  the  eye 
occurs.  In  such  cases  an  elevation  in  body  temperature  may 
occur.  This  is  especially  true  of  purulent  conjunctivitis  when 
primarily  caused  by  an  infectious  agent.  In  the  purulent  form 
the  discharge  is  heavy  and  pus-like. 

The  treatment  is  both  preventive  and  curative.  The  first 
object  must  be  to  remove  the  cause.  Irritating  gases  resulting 
from  stable  filth  should  be  remedied  by  correcting  the  unsani- 
tary conditions  in  the  stable.  Conditions  favoring  injury  to  the 
eye  from  foreign  bodies,  such  as  chaff  and  a  careless  attendant, 
should  be  corrected.  Animals  suffering  from  the  infectious 
or  purulent  form  of  inflammation  should  be  separated  from  the 
other  animals.  Foreign  bodies  should  be  removed  promptly  be- 
fore they  have  had  an  opportunity  to  set  up  a  serious  inflam- 


128  NON-SPECIFIC  OR  GENERAL  DISEASES 

niation.  It  is  necessary  to  confine  the  animal  in  some  way  before 
attempting  to  do  this.  Horses  should  be  twitched,  cattle  held  by 
the  nose,  and  the- head  of  a  small  animal  held  firmly  with  the 
hands.  It  may  be  necessary  to  cocainize  the  eye  before  the  oper- 
ator can  remove  the  foreign  object  with  absorbent  cotton  or  with 
forceps. 

In  case  of  injuries  and  irritation  to  the  lids  by  foreign  bodies, 
the  eye  may  be  flooded  with  a  three  per  cent  water  solution  of 
boric  acid  twice  daily,  or  as  often  as  necessary.  Such  washes  or 
lotions  may  be  applied  with  a  small  piece  of  absorbent  cotton, 
using  a  fresh  piece  each  time  the  eye  is  dressed.  A  medicine 
dropper  may  also  be  used.  A  lotion  containing  silver  nitrate 
two  to  four  grains  and  distilled  water  one  ounce,  is  useful  in 
combating  the  inflammation.  This  may  be  applied  twice  daily. 
Irritating  lotions  should  be  avoided,  if  possible,  in  the  treat- 
ment of  eye  diseases  of  horses,  because  of  the  danger  of  making 
the  animal  disagreeable  to  handle.  Boric  acid  may  be  dusted 
over  the  ball  of  the  eye  of  cattle  with  a  powder  blower. 

Periodic  Ophthalmia,  "  Moonblindness." — This  is  a  peri- 
odic inflammation  of  one  or  both  eyes  of  the  horse.  The  internal 
structures  of  the  eye  are  involved  by  the  inflammation,  but  it 
may  appear  as  a  conjunctivitis. 

The  cause  of  this  disease  is  not  well  understood.  Certain 
local  conditions  seem  to  favor  its  development.  Undrained  land, 
a  humid  climate,  the  feeding  of  a  one-sided  ration  or  one  that 
does  not  maintain  the  vitality  of  the  animal,  and  severe  work 
seem  to  produce  it.  Heredity  must  be  accepted  as  a  prominent 
accessory  cause.  A  number  of  diflerent  bacteria  have  been 
mentioned  as  causative  factors  for  this  disease. 

The  symptoms  at  the  very  beginning  indicate  a  general  in- 
flammation of  the  eye.  The  eyelids  are  swollen,  there  is  an 
abundant  secretion  of  tears,  the  eyeball  is  retracted  and  the  lids 
are  held  more  or  less  closed.  As  the  inflammation  progresses, 
the  cornea  becomes  milky  in  appearance  and  the  aqueous  humor 


DISEASES  OF  THE  EYE  129 

may  show  a  precipitate  toward  the  bottom  of  the  anterior 
chamber.  The  pupil  is  usually  contracted  and  dilates  slowly 
when  the  animal  is  moved  into  the  light.  The  acute  inflammation 
gradually  subsides,  and  about  the  tenth  to  the  fourteenth  day 
the  lids  and  cornea  may  appear  normal. 

The  periods  between  these  acute  attacks  of  ophthalmia  may 
vary  from  a  few  weeks  to  several  months.  Severe  work,  debility 
and  the  character  of  the  ration  influence  their  frequency.  It 
is  not  uncommon  for  animals  that  have  been  given  a  rest  to  suffer 
from  a  second  attack  on  being  put  to  work.  The  attendant  may 
observe  a  hazy  or  whitish  condition  of  the  margin  of  the  cornea. 
The  upper  lid  may  show  an  abrupt  bend  of  its  margin  and  a  deep 
wrinkle.  The  color  of  the  iris  appears  to  have  lost  its  lustre,  and 
the  aqueous  humor  and  lens  may  be  cloudy.  After  a  variable 
number  of  attacks  glaucoma  or  cataract  develops. 

The  history  of  the  case  will  enable  the  attendant  to  recognize 
this  form  of  Oi^hthalmia. 

Treatment  is  unsatisfactory.  Preventive  measures  consist 
in  avoiding  conditions  favorable  to  the  production  of  the  disease. 
This  should  be  practised  so  far  as  possible.  At  the  time  the 
attack  occurs,  the  animal  should  be  given  a  cathartic.  One  pound 
of  Glauber's  salts  in  a  drench  is  to  be  preferred.  Eest  in  a 
darkened  stall  is  indicated.  An  eye  lotion  containing  three 
grains  of  silver  nitrate  in  one  ounce  of  distilled  water  should 
be  applied  to  the  eye  three  times  daily.  A  water  solution  of 
atropine  or  eserine  should  be  used  for  the  purpose  of  relieving 
the  spnptoms  of  iritis  or  glaucoma.     A  very  light  diet  should 

be  fed. 

Infectious  Ophthalmia  of  Ruminants. — This  occurs  as  an 
acute  inflammation  of  the  eyelids  and  cornea.  The  disease  is 
highly  infectious,  affecting  all  of  the  susceptible  animals  in  the 
herd.     It  commonly  occurs  during  the  late  summer  and  fall. 

The  symptoms  appear  suddenly.  The  animal  is  feverish, 
the  eyes  closed  and  the  cheeks  are  wet  with  tears.  The  cornea 
9 


130  NON-SPECIFIC  OR  GENERAL  DISEASES 

becomes  clouded,  white  and  opaque.  In  severe  cases,  the  blood- 
vessels around  the  margin  of  the  cornea  become  prominent, 
and  ulcers  form  on  its  surface.  The  animal's  appetite  is  impaired 
or  lost.  There  is  loss  of  flesh  and  temporary  blindness.  The 
blindness  in  one  or  both  eyes  may  persist  for  a  period  of  from 
two  weeks  to  several  months.  Permanent  blindness  is  com- 
paratively rare. 

The  preventive  treatment  consists  in  practising  the  necessary 
precautions  against  the  introduction  of  the  disease  into  the  herd, 
and  in  carefully  quarantining  the  first  cases  of  the  disease  that 
appear.  The  affected  animal  should  be  given  a  darkened  stall, 
and  fed  a  very  light  ration  until  the  acute  inflammation  has 
subsided.  From  one  to  one  and  one-half  pounds  of  Glauber's 
salts  should  be  given.  The  loeal  treatment  consists  in  the  appli- 
cation of  antiseptic  lotions  or  powders  to  the  eye.  Equal  parts 
of  boric  acid  and  calomel,  dusted  into  the  eye  twice  daily  with 
a  powder  blower,  is  a  very  effective  treatment. 

QUESTIONS 

1.  Name  the  different  structvires  that  form  the  shell  of  the  eye:  name  and 

describe  the  different  media  of  the  eye. 

2.  Give  the  general  method  of  examining  the  eyes  of  horses. 

3.  What  is  conjunctivitis?     Give  causes  and  treatment. 

4.  What  is  "  moonhlindness  "?    Give  the  symptoms. 

5.  Describe  the  symptoms  of  infectious  ophthalmia  of  ruminants  and  the 

treatment. 


CHAPTER  XIII 

GENERAL  DISEASES  OF  THE  LOCOMOTORY  APPARATUS 

General  Discussion. — The  movements  of  the  different  parts 
of  the  animal  body  depend  on  the  nnion  of  the  bones  that  form 
the  skeleton  (Fig.  2S),  and  mode  of  insertion  of  the  muscles. 
The  bones  meet  and  form  joints  or  articulations.     These  are 


Fig.  28. — Skeleton  of  horse. 

divided  into  three  clases:  movable,  mixed  and  immovable. 
Nearly  all  of  the  articulations  in  the  extremities  belong  to  the 
movable  class.  The  articulations  between  the  bodies  of  the 
vertebrffi  belong  to  the  mixed,  and  those  between  the  flat  bones 
of  the  head  to  the  immovable  class. 

The  bony  surfaces  that  meet  and  form  the  different  types  of 
articulations  are  held  together  by  ligaments  (Fig.  20).     Some- 

131 


132 


NON-SPECIFIC  OR  GENERAL  DISEASES 


times  the  ligament  is  placed  between  the  bony  surfaces,  but 
usually  it  is  attached  to  the  margins  of  the  articular  surfaces 
that  it  unites.  The  immovahle  class  possesses  fibrous-like  liga- 
ments that  are  placed  between  the  margins  of  the  flat  bones  that 
form  the  articulation.  The  mixed  articulations  are  united  by  a 
fibro-cartilaginous  pad  that  is  firmly  attached  to  the  articular 

faces  of  the  bones,  and  by 
peripheral  ligaments  that  may 
be  flat  or  formed  by  scattered 
fibres.  All  movaljle  articu- 
lations are  formed  by  bony 
surfaces  encrusted  with  a 
thin  cartilaginous  layer  that 
makes  them  perfectly  smooth, 
ligaments  and  complimentary 
cartilages.  Sometimes  the 
bony  surfaces  do  not  fit  each 
other,  and  we  find  between 
them  fihro-cartilages  that  com- 
plete the  articulation  by 
adapting  the  articular  sur- 
faces to  each  other.  Round 
or  flat  ligaments  may  extend 
from  one  articular  surface  to 
the  other,  and  attached  to  the 
margins  of  the  articulation 
are  membranous,  flat  or  round  ligaments.  Muscles  and  tendons 
that  cross  the  articulations  should  be  included  among  the 
structures  binding  them  together. 

Movable  joints  possess  a  synovial  membrane.  This  mem- 
brane lines  the  structures  that  enclose  the  articulation  and 
secretes  a  fluid,  the  synovia,  that  lubricates  the  surfaces. 

The  muscles  are  the  contractile  organs  that  move  the  body. 
The  movement  of  the  different  parts  of  the  body  is  rendered 


Fig.  29. — Photograph  of  model  of  stifle  joint, 
showing  (I,  P)  ligaments;  (L)  complementary- 
cartilages;  (K)  femur;  and  (R)  tibia. 


GENERAL  DISEASES  OF  THE  LOCOMOTORY  APPARATUS  133 

possible  through  the  iiianiier  in  which  the  skeletal  imiscles  are 
inserted  into  the  long  bones,  by  which  the  lever  motion  is  pos- 
sible. A  muscle  originating  on  one  bone  and  terminating  on 
another  either  moves  both  bones  toward  each  other  or,  if  one 
attachment  is  fixed,  the  movable  is  drawn  toward  the  fixed  part. 

We  maj  class  muscles  as  striated  or  voluntary  and  unstriated 
or  involuntary.  A  third  class,  rnixed,  is  represented  by  the  heart 
muscle.  The  striated  is  represented  by  the  skeletal  muscles,  and 
the  unstriated  by  the  thin  muscular  layers  that  form  part  of  the 
wall  of  the  stomach,  intestines,  bladder  and  other  hollow  organs. 

Rheumatism. — This  is  an  inflammation  of  the  tissues  that 
form  the  locomotory  apj)aratus.  The  effect  of  cold  on  the 
muscles  and  tendons  is  an  important  factor  in  its  production. 
It  differs  from  other  inflammations  by  shifting  from  one  part 
to  another.  It  is  termed  muscular  rheumatism  w^hen  it  afl'ects 
the  muscles,  tendons  and  fascia,  and  articular  rheumatism  when 
it  involves  the  articulations.  A  second  classification,  acute  and 
chronic,  depends  on  the  character  of  the  inflammation.  The 
muscular  form  is  common  in  horses,  dogs  and  hogs,  while  the 
articular  form  more  commonly  affects  cattle. 

The  following  causes  may  be  considered.  Animals  that  are 
exposed  to  cold,  wet,  changeable  weather,  or  kept  in  cold,  damp, 
draughty  quarters  frequently  suffer  from  rheumatism.  Under 
such  conditions  it  is  very  probable  that  imperfect  metabolism  of 
body  tissue  occurs,  and  certain  toxic  products  that  are  capable  of 
irritating  the  muscles  and  articulations  form.  Clinical  symp- 
toms, and  the  presence  of  bacteria  in  the  inflamed  tissue  indi- 
cate that  bacteria  and  their  toxins  play  an  important  part  in  the 
development  of  articular  rheumatism.  Heredity  is  said  to  be 
an  important  predisjDosing  factor.  One  attack  always  predis- 
poses the  animal  to  a  second. 

The  symptoyns  vary  according  to  the  severity  of  the  attack. 
Local  rheumatism  is  not  accompanied  by  serious  s^anptoms.  The 
regions  most  commonly  involved  in  local,  muscular  rhemnatism 


134  NON-SPECIFIC  OR  GENERAL  DISEASES 

are  the  shoulder,  neck  and  back.  The  joints  affected  in  the 
articular  form  are  the  knee,  fetlock,  hip,  elbow  and  shoulder. 
The  attack  is  usually  sudden  and  accompanied  by  fever,  more 
or  less  loss  of  appetite  and  soreness.  Loss  of  control  over  the 
movement  of  the  hind  parts  or  walking  on  the  knees  may  occur 
in  the  smaller  animals.  The  larger  animals  show  a  slight  or 
severe  lameness.  The  affected  muscle  or  articulation  may  be 
swollen,  hot  and  tender.  Pressing  on  the  part  with  the  hand  or 
forcing  the  animal  to  move  about  may  cause  severe  pain.  Weak- 
ness and  emaciation  may  occur  in  generalized  and  articuLir 
rheumatism,  especially  if  suppuration  takes  place  in  the  affected 
joint. 

The  prognosis  is  more  favorable  in  muscular  rheumatism 
than  in  the  articular  form.  Both  forms  may  become  chronic. 
It  is  frequently  advisable  to  destroy  animals  suffering  from  the 
articular  form  because  of  their  emaciated,  weakened  condition 
and  the  deformed  condition  of  the  joints. 

The  preventive  treatment  consists  in  avoiding  conditions  fa- 
vorable to  the  production  of  rheumatism.  In  ventilating  the  stable 
we  should  avoid  draughts.  Practical  experience  indicates  that 
allowing  a  horse  to  stand  in  a  draught  after  it  has  been  warmed 
up  by  exercise  is  a  very  common  source  of  muscular  rheumatism 
and  is  especially  to  be  avoided.  Young  hogs  and  sows  that  are  thin 
are  very  prone  to  rheumatism  when  given  wet,  draughty  sleeping 
quarters.  Houses  having  dirt  or  loose  board  floors  are  very  often 
draughty.  Concrete  floors  when  wet  and  not  properly  bedded 
with  straw  are  objectionable.  Although  we  do  not  fully  under- 
stand the  causative  factors,  we  can  take  advantage  of  the  knowl- 
edge we  have  gained  from  practical  experience,  and  avoid  keep- 
ing animals  under  conditions  that  are  favorable  for  the  produc- 
tion of  the  disease.  It  is  almost  useless  to  treat  rheumatism 
unless  the  conditions  under  which  it  occurred  are  corrected. 

Tlie  treatment  is  both  local  and  internal.  The  local  treat- 
ment consists  in  applying  a  mild  liniment  to  the  part,  together 
with  massage.    If  the  part  is  tender  and  painful,  hot  applications 


GENERAL  DISEASES  OF  THE  LOCOMOTORY  APPARATUS  135 

may  be  used.  Spirits  of  camphor  ten  parts  and  turpentine  two 
parts,  applied  daily,  are  useful  in  relievinc^  the  soreness  of 
rheumatic  muscles.  Salicylate  of  soda  two  ounces,  fluid  extract 
of  gentian  one  ounce,  and  sufficient  water  to  make  an  eight-ounce 
mixture  may  he  given  internally  three  times  daily  after  feeding. 
Of  the  above  mixture  horses  and  cattle  may  be  given  one-half 
ounce  and  sheep  and  swine  from  one  to  two  drachms.  The 
treatment  should  be  continued  for  a  period  of  from  eight  to  ten 
days  or  longer.     It  may  be  repeated  in  from  one  to  two  weeks. 


Fia.  30.— Atrophy  of  the  muscles  of  the  thigh  resulting  from  an  attack  of  azoturia. 

Iodide  of  potassium  is  very  useful  in  the  treatment  of  chronic 
articular  rheumatism.  A  very  light  diet  should  be  fed  and  the 
animal  given  as  complete  rest  as  possible.  An  occasional  physic 
should  be  given. 

Azoturia,  Haemoglobinuria. — This  is  a  disease  of  solipeds 
affecting  the  muscles  of  the  quarters.  The  affected  muscles 
become  swollen,  hard  and  paralyzed.  The  disease  follows  a 
short  rest,  and  rarely  occurs  when  the  animal  is  running  in 
pasture  or  idle  for  a  long  period.  Animals  that  are  fat  or 
rapidly  putting  on  fat  are  predisposed  to  it.  Animals  that  have 
Lad  one  attack  are  predisposed  to  a  second. 


136  NON-SPECIFIC  OR  GENERAL  DISEASES 

The  cause  of  this  disease  is  not  positively  known.  The  Ger- 
man veterinarians  attribute  it  to  irritation  of  the  muscles  by 
cold,  and  classify  azoturia  as  a  rheumatic  disorder.  The  con- 
ditions preceding  the  attack  are  not  in  favor  of  this  theory, 
and  cold  can  not  be  considered  an  important  causative  factor. 
The  most  acceptable  is  the  auto-poisoning  theory  advanced  by 
Dr.  Law. 

Azoturia  is  common  in  the  country  where  feed  is  abundant 
and  wrong  methods  of  feeding  horses  are  commonly  practised. 
It  is  a  very  common  practice  to  feed  horses  accustomed  to  hard 
work  the  same  ration  when  idle  for  a  few  days  as  when  working. 
The  blood  of  horses  cared  for  in  this  way  may  become  abnor- 
mally rich  in  albuminoids.  The  suddenness  of  the  attack,  occur- 
ring shortly  after  the  animal  is  given  exercise,  indicates  auto- 
poisoning.  This  may  be  due  to  the  blood  in  the  portal  vessels 
and  the  liver  capillaries,  charged  Avith  nutritious  and  waste  prod- 
ucts from  the  overfed  animal's  intestines,  being  suddenly  thrown 
into  the  general  circulation  by  a  more  active  circulation  of  the 
blood  brought  on  by  exercise. 

The  symptoms  of  disease  are  manifested  shortly  after  the 
animal  is  moved  out  of  the  stall  and  given  exercise.  When  the 
animal  is  first  exercised  it  is  usually  in  high  spirits.  After 
travelling  a  short  distance  it  is  noticed  to  sweat  more  freely 
than  ordinarily,  breathe  rapidly,  lag  and  go  lame,  usually  in  the 
hind  limbs.  It  trembles,  shows  evidence  of  suffering  severe  pain 
by  turning  its  head  and  looking  around  toward  the  flanks, 
knuckles  over  in  the  hind  pasterns,  and  may  fall  down  and  be 
unable  to  get  up.  The  affected  muscles  appear  to  be  swollen  and 
feel  unusually  firm  when  pressed  upon  with  the  hand.  If  the 
horse  does  not  go  down  recovery  may  occur  within  a  few  hours, 
and  we  are  able  to  move  the  horse  to  the  stable.  Dark  brown 
urine  may  be  passed.  At  other  times,  the  animal  lies  in  a  natural 
position,  possesses  a  good  appetite,  but  can  not  stand.  In  the 
severe  form,  it  is  restless  and  shows  marked  nervous  symptoms. 


GENERAL  DISEASES  OF  THE  LOCOMOTORY  APPARATUS  137 

The  prognosis  is  unfavorable  in  the  severe  form.  When 
nervous  s;^Tnptoms  are  absent  recovery  usually  occurs  in  from 
two  to  ten  days.  Complications  are  common.  More  or  less 
atrophy  of  the  muscles  of  the  quarters  may  result  (Fig.  30). 

The  preventive  treatment  consists  in  avoiding  conditions  that 
may  favor  the  production  of  the  disease.  ]\Iore  attention  should 
be  given  the  feeding  and  care  of  work  animals.  If  it  is  not  pos- 
sible to  permit  horses  that  are  worked  to  exercise  in  a  lot  or 
pasture  when  idle,  the  ration  should  be  reduced  and  roots, 
chopped,  or  soft  feed  given. 

Careful  nursing  is  an  important  part  of  the  ireatment.  As 
soon  as  the  horse  shows  evidence  of  an  attack,  it  should  be  stopped 
and  allowed  to  stand  until  sufficiently  recovered  to  be  moved. 
If  paralysis  occurs,  we  should  make  it  as  comfortable  as  possible 
and  arrange  to  move  it  to  a  comfortable,  warm,  well-bedded  stall. 
It  may  be  advisable  to  place  the  animal  in  slings.  This  is  not 
advisable  in  the  serious  form  of  the  disease  because  of  the  extent 
of  the  paralysis  and  the  nervous  s^miptoms.  A  very  light  diet, 
bran  mashes,  chopped  hay  or  green  feed,  should  be  fed  during 
the  convalescent  period  and  for  several  days  after  complete 
recovery  has  occurred. 

The  following  lines  of  medicinal  treatment  may  be  recom- 
mended. We  should  endeavor  to  stimulate  the  elimination  of 
the  waste  products  from  the  body  by  way  of  the  kidneys,  intes- 
tines and  skin.  This  may  be  accomplished  by  administering 
saline  cathartics,  covering  the  body  with  blankets,  encouraging 
the  animal  to  drink  plenty  of  water  and  feeding  soft  feeds. 
Glauber's  salts  may  be  given  as  a  drench,  or  eserine  may  be  given 
hypodermically.  Sedatives  such  as  chloral  hydrate  may  be  used 
to  quiet  the  animal. 

QUESTIONS 

1.  Give  a  general  description  of  the  locomotory  apparatus. 

2.  Give  the  causes  of  rheumatism:  describe  the  treatment. 

3.  What  is  azoturia?     Give  the  cause  of  this  disease. 


CHAPTER  XIV 
STRUCTURE  OF  THE  LIMBS  OF  THE  HORSE 

General  Discussion. — Each  limb  is  formed  bv  a  column  of 
bones  that  rest  upon  one  another,  forming  more  or  less  open 
angles.  The  bones  of  the  column  meet  and  form  articulations 
that  are  held  together  bv  ligaments,  and  attached  to  their  faces, 
borders  and  extremities  are  muscles  and  tendons.  In  the  superior 
portion  of  the  limb  the  muscles  are  heavy,  tapering  inferiorly, 
and  terminating  in  the  region  of  the  foot  in  long  tendons. 
Each  limb  is  divided  into  four  regions.  The  regions  of  the  fore- 
Umh  are  the  shoulder,  arm,  forearm  and  forefoot.  In  the  hind 
limh  are  the  regions  of  the  pelvis,  haunch,  thigh,  leg  and  hind- 
foot.  The  feet  in  turn  are  divided  into  three  sub-regions  each. 
The  forefoot  is  formed  by  the  knee,  cannon  and  toe,  and  the 
liindfoot  by  the  hock,  cannon  and  toe. 

The  shoulder  bone  or  scapula  is  flat  and  triangular  in  shape. 
It  is  attached  to  the  trunk  by  heavy  muscles,  one  of  which,  to- 
gether with  its  fellow  on  the  opposite  side,  may  be  compared 
to  a  great,  muscular  sling  that  supports  about  two-thirds  of  the 
body  weight.  Attached  to  the  internal  and  external  faces  of 
the  scapula  are  heavy  muscles  that  pass  over  the  shoulder-joint, 
and  become  attached  to  the  arm  bone  through  the  insertion  of 
their  muscular  fibres  or  by  a  short  tendon. 

The  arm  bone  or  humerus  belongs  to  the  class  of  long  bones. 
Its  superior  extremity  forms  a  flattened  head  that  fits  rather 
imperfectly  into  a  shallow  cavity  in  the  humeral  angle  of  the 
scapula.  The  inferior  extremity  resembles  a  portion  of  a  cylin- 
der in  shape,  and  fits  into  shallow  depressions  in  the  superior 
extremity  of  the  principal  bone  of  the  forearm.  The  muscles 
here  are  divided  into  two  regions,  anterior  and  posterior  brachial. 
The  most  of  these  muscles  originate  on  the  posterior  border  and 
138 


STRUCTURE  OF  THE  LIMBS  OF  THE  HORSE  139 

inferior  extremity  of  the  shoulder  bone,  and  terminate  inferiorly 
on  the  superior  extremities  of  the  principal  and  second  or  rudi- 
mentary bone  of  the  forearm.  The  posterior  brachial  muscles 
are  heavy  and  powerful.  They  are  sometimes  termed  elbow 
muscles,  because  they  are  attached  to  the  point  of  the  elbow. 

The  region  of  the  forearm  is  formed  by  two  bones,  the 
radius  and  ulna.  The  radius  is  the  principal  bone  and  is  classed 
among  the  long  bones.  The  ulna  is  an  elongated  flat  bone.  It  is 
attached  to  the  external  portion  of  the  posterior  face  of  the 
radius  and  extends  above  the  superior  extremity  of  this  bone 
to  form  the  point  of  the  elbow.  The  radius  articulates  with  the 
upper  row  of  knee  bones.  The  muscles  of  this  region,  the  anti- 
brachial,  are  divided  into  two  sub-regions,  anterior  and  pos- 
terior. They  originate  superiorly  from  the  lower  extremity 
of  the  arm  bone  and  the  superior  extremities  of  the  bones  of  the 
forearm,  and  terminate  toward  the  lower  extremity  of  the  region 
in  tendons  that  become  attached  to  the  bones  of  the  knee,  cannon 
and  digit. 

The  knee  or  carpal  region  is  formed  by  seven  short  bones 
that  are  arranged  in  two  rows.  They  form  a  series  of  articu- 
lations. These  are  the  articulations  between  the  two  rows,  be- 
tween the  bones  of  each  row,  and  between  the  upper  and  lower 
rows  and  the  neighboring  regions.  jSTearly  all  the  motion  takes 
place  in  the  articulation  between  the  upper  row  and  the  principal 
bone  of  the  forearm. 

The  cannon  or  metacarpal  region  is  formed  by  three  bones. 
These  are  the  principal  metacarpal  or  cannon  bone,  and  the  rudi- 
mentary  metacarpal  or  splint  bones.  The  latter  are  attached 
to  the  margins  of  the  posterior  face  of  the  cannon  bone.  The 
superior  extremities  of  these  bones  articulate  with  the  lower  row 
of  carpal  bones.  The  convex  extremity  of  the  cannon  bone  meets 
shallow  depressions  in  the  superior  extremity  of  the  first  digital 
bone.     This  is  termed  the  fetlock  joint.     The  anterior  and  pos- 


140  NON-SPECIFIC  OR  GENERAL  DISEASES 

terior  faces  of  this  region  are  travelled  by  the  long  tendons 
belonging  to  the  extensor  and  flexor  muscles  of  the  digit. 

The  digit  or  toe  is  formed  by  six  bones,  three  of  which  are 
termed  accessory  or  sesamoids.  The  digital  bones  may  be  given 
numerical  names. 

The  approximal  or  first  digital  bone  is  the  shortest  long 
bone  in  the  bodv.  The  two  shallow  articular  cavities  belonging 
to  the  superior  extremity  are  completed  posteriorly  by  the  two 
sesamoid  bones.  The  inferior  extremity  is  smaller  than  the 
superior  and  resembles  the  inferior  extremity  of  the  cannon 
bone  in  shape,  excepting  that  it  shows  a  middle  groove.  The 
anterior  and  posterior  faces  are  travelled  by  the  tendons  of  the 
digital  muscles. 

The  middle  or  second  digital  bone  is  quite  short.  It  articu- 
lates superiorly  with  the  first,  and  inferiorly  with  the  third  bone 
of  the  digit.  The  superior  face  shows  two  shallow  cavities,  and 
the  inferior  two  convex  surfaces  separated  by  a  median  groove. 
The  latter  face  articulates  with  the  third  and  navicular  bones. 
The  popular  name  for  this  articulation  is  the  coffin  joint. 

The  third  or  distal  digital  bone  may  be  compared  to  a  cone 
that  has  been  cut  away  posteriorly,  obliquely  downwards  and 
backwards.  The  superior  face  shows  two  shallow  cavities  that 
are  completed  posteriorly  by  the  superior  face  of  the  cofiin  or 
navicular  bone.  The  anterior  face  is  convex  and  cribblod  by 
openings,  and  the  inferior  face  is  concave,  forming  the  sole. 
Tendons  belonging  to  the  digital  muscles  terminate  on  the  sum- 
mit and  inferior  face  of  this  bone. 

The  pelvis  or  haunch  is  formed  by  a  single  bone,  the  coxa, 
that  in  the  foetus  may  be  divided  into  three  bones.  These  are  the 
ilium,  pubis  and  ischium.  It  belongs  to  the  class  of  flat  bones. 
Anteriorly  it  is  flattened  from  before  to  behind  and  directed 
inward  and  upward.  The  external  angle  is  rugged  and  is  gener- 
ally termed  the  angle  of  the  haunch.  The  internal  face  of  the 
opposite  angle  articulates  with  the  sacrum,  to  which  it  is  firmly 


STRUCTURE  OF  THE  LIMBS  OF  THE  HORSE  141 

attached  by  ligaments.  The  middle  portion  is  constricted  and 
forms  a  neck.  The  inferior  or  posterior  portion  is  flattened 
from  above  to  below,  and  directed  inward  to  meet  the  border 
of  the  opposite  bone.  Just  below  the  neck  and  externally,  there 
is  a  cup-shaped  cavity  into  which  the  head  of  the  thigh  bone 
fits.  The  two  coxa,  together  with  the  sacral  ligaments  (sacrum) 
and  the  muscles  of  the  quarter,  enclose  the  pelvic  cavity. 

The  region  of  the  thigh  is  formed  by  the  femur,  the  largest 
long  bone  in  the  body.  The  superior  extremity  is  formed  by  a 
rugged  eminence,  to  which  the  heavy  muscles  of  the  quarter  are 
attached,  and  by  an  articular  head.  The  inferior  extremity  is 
formed  by  two  convex  articular  surfaces  that  are  separated  by 
a  deep  notch,  and  a  third  pulley-like  articular  surface,  with  which 
the  patella  or  knee-cap  articulates.  The  pair  of  condyles  articu- 
lates with  the  superior  extremity  of  the  leg  bone.  The  thigh 
or  femoral  region  is  heavily  muscled. 

The  leg  is  formed  by  three  bones.  The  patella,  a  short  bone, 
has  already  been  mentioned  as  articulating  with  the  thigh  bone. 
The  tibia  and  fibula  are  the  other  two  bones  in  the  region. 

The  tibia  belongs  to  the  class  of  long  bones  and  the  fibula 
is  quite  rudimentary,  being  represented  by  a  stylet-shaped  bone 
that  lies  posterior  to,  and  along  the  outer  border  of  the  tibia. 
The  superior  extremity  of  the  tibia  shows  a  central  spine  mar- 
gined laterally  by  rather  plain  articular  faces.  It  articulates 
with  the  thigh  bone.  The  muscles  of  this  region  are  divided 
into  two  sub-regions,  anterior  and  posterior  tibial.  The  muscles 
originate  from  the  lower  extremity  of  the  femur  and  the  two 
bones  in  this  region,  and  terminate  inferiorly  in  tendons  that  are 
attached  to  the  bones  of  the  hock,  cannon  and  digit. 

The  hock  or  tarsal  region  is  formed  by  six  bones.  They  are 
described  as  forming  two  rows.  In  the  upper  row  there  are  two 
bones  and  in  the  lower  four.  They  form  a  series  of  articulations, 
the  same  as  the  bones  of  the  knee.  Practically  all  of  the  move- 
ment occurs  in  the  articulation  between  one  of  the  large  bones 


142  NON-SPECIFIC  OR  GENERAL  DISEASES 

in  tlie  upper  row  and  the  lower  extremity  of  the  tibia.  It  may 
be  mentioned  here  that  this  is  the  most  perfect  hinge-joint  in  the 
body.  A  very  large  tendon  is  attached  to  the  summit  of  the  hock. 
Other  tendons  cross  and  become  attached  to  the  hock  bones. 

The  regions  of  the  hiiid  cannon  and  digit  are  practically  the 
same  as  the  corresponding  regions  of  the  forefoot. 

QUESTIONS 

1.  Name   the   different   bones  of  the   fore-limb;    hind   limb. 

2.  Describe  the  regions  of  the  shoulder,  arm  and  forearm. 

3.  Describe  the  region  of  the  forefoot. 

4.  Describe  the  regions  of  the  haunch,  thigh  and  leg. 

5.  Describe  the  region  of  the  hindfoot. 


CHAPTER  XV 

UNSOUNDNESSES  AND  BLEMISHES 

General  Discussion. — The  value  of  a  horse  depends  largelj- 
on  the  condition  of  the  limbs  and  their  ability  to  do  the  work 
for  which  they  are  intended.  This  fact  is  frequently  overlooked 
by  experienced  horsemen,  who  give  attention  to  general  confor- 
mation and  action  rather  than  to  soundness  of  limb. 

Diseases  affecting  the  limbs  may  be  classed  as  unsoundnesses 
and  blemishes.  This  classification  is  based  on  the  degree  to 
which  the  disease  interferes  or  may  interfere  with  the  work  that 
the  animal  is  called  on  to  perform.  Unsoundnesses  interfere  with 
the  use  of  the  part  or  the  use  of  the  animal  for  a  certain  work ; 
blemishes  do  not.  Such  a  basis  for  the  classification  of  diseases 
does  not  enable  us  to  place  certain  diseased  conditions  of  the 
limbs  in  tlie  unsound,  or  the  blemish  class  at  all  times.  A  curb 
may,  if  it  produces  lameness,  be  classed  as  an  unsoundness.  If 
it  does  not  cause  the  animal  to  go  lame,  and  the  enlargement  on 
the  posterior  border  of  the  hock  is  small,  it  is  classed  as  a 
blemish.  A  high  splint  may  place  the  animal  in  the  unsound 
class,  but  usually  a  low  splint  is  not  considered  a  serious  blemish. 
This  classification  is  based  to  a  certain  extent  on  the  relative 
economic  importance  of  the  disease,  or  the  influence  that  the 
disease  may  have  on  the  value  of  the  animal,  as  well  as  any  inter- 
ference with  the  animal's  ability  to  work. 

Recognition  of  the  Disease. — The  seat  of  the  disease  may 
be  in  a  muscle,  tendon,  bone  or  ligament.  The  general  s}anp- 
tom  manifested  is  lameness  or  pain.  The  local  symptoms  are 
heat,  pain,  swelling  and  bony  enlargements.  The  degree  of 
lameness  and  the  character  of  the  local  lesions  vary  greatly  in 
the  different  cases.  Wlien  the  animal  show^s  a  slight  lameness 
and  there  is  little  evidence  of  any  local  symptom,  it  requires 

143 


144  NON-SPECIFIC  OR  GENERAL  DISEASES 

the  services  of  a  skilled  and  experienced  person  to  locate  tlie 
diseased  part.  Wlien  the  part  shows  local  lesions  of  disease  and 
the  lameness  is  characteristic,  diagnosis  is  not  difficult. 

The  examination  should  he  made  while  the  animal  is  at  rest; 
while  standing  in  the  stall  and  on  level  ground  ;  when  moved  at  a 
walk,  or  a  slow  trot  on  soft  ground,  or  a  hard  roadway ;  and  whetn 
moved  out  after  resting  a  few  hours.  While  examining  the 
animal  under  the  different  conditions  mentioned,  the  examiner 
must  be  careful  and  not  pass  over  any  part  of  a  limb  without 
determining  whether  it  is  normal  or  not.  He  should  note  any 
abnormal  position  that  the  animal  may  take  while  standing  at 
rest.  Every  movement  should  be  watched  closely,  as  the  manner 
of  favoring  the  part  may  characterize  the  lameness.  Negative 
symptoms  of  lameness  in  a  part  may  at  times  prove  as  valuable 
in  forming  a  diagnosis  as  positive  symptoms. 

The  resting  of  either  of  the  front  feet,  when  the  horse  is 
standing  at  ease,  indicates  that  there  is  some  soreness  in  the 
rested  limb.  Pointing  or  placing  one  or  both  feet  well  in  front 
of  the  line  of  support,  when  the  animal  is  standing,  usually  indi- 
cates a  diseased  condition  of  the  feet.  It  is  natural  for  a  horse 
that  is  standing  in  a  stall  to  rest  the  hindfeet  alternately.  When 
the  hindfoot  is  rested  because  of  a  soreness  in  some  portion  of 
the  limb,  it  may  be  flexed  or  extended,  the  weight  rested  on  the 
toe,  and  the  foot  flexed  and  bearing  practically  no  weight.  In 
serious  inflammation  of  the  front  feet,  both  feet  may  be  placed 
well  in  front  of  the  nonnal  position,  and  the  hindfeet  well  under 
the  body. 

When  examining  a  horse,  the  blanket  or  harness  should  be 
removed.  The  horse  should  have  on  an  open  bridle  or  halter,  and 
the  attendant  should  give  it  as  much  freedom  of  the  head  as 
possible.  The  examiner  should  examine  each  limb  carefully  and 
note  any  s;>anptom  of  disease  that  may  be  present.  The  attendant 
should  walk  the  animal  straight  away  from  the  person  making 
the  examination,  toward,  and  past  him,  so  that  the  animal's 


UNSOUNDNESSES  AND  BLEMISHES  145 

movements  cau  be  observed  from  both  sides,  from  behind  and  in 
front.  This  examination  should  be  repeated  with  the  horse  at 
a  slow  trot. 

The  character  of  the  lameness  may  enable  us  to  locate  the 
seat  of  the  disease.  We  must  first  determine  in  which  limb  the 
animal  is  lame.  This  part  of  the  diagnosis  is  not  ditHcult.  The 
pain  suffered  every  time  weight  is  thrown  on  tlie  diseased  limb 
causes  the  horse  to  step  quickly  and  shift  as  much  of  the  body 
weight  as  possible  on  the  well  foot.  The  foot  of  the  lame  limb 
is  jerked  up  rather  (juickly  after  weight  is  thro\\m  on  it.  This 
favoring  of  the  part  varies  in  the  different  diseases.  When  the 
foot  of  the  sound  limb  comes  to  the  ground,  more  weight  than 
common  is  placed  on  it.  If  the  seat  of  the  lameness  is  in  a  front 
limb,  there  is  a  decided  nodding  or  movement  of  the  head  down- 
ward when  the  weight  is  placed  on  the  well  foot.  If  both  fore- 
feet are  diseased,  the  animal  steps  shorter  and  more  quickly  than 
common.  Lameness  in  a  hind  limb  is  characterized  by  more  or 
less  dropping  of  the  quarter  of  the  well  limb  when  weight  is 
thrown  on  it,  and  sometimes  by  a  "  hitch  "  or  elevation  of  the 
quarter  of  the  diseased  limb  when  it  is  carried  forward. 

Unless  there  are  local  symptoms  of  disease  present,  it  may 
be  quite  difficult  to  locate  the  seat  of  lameness.  Sometimes  local 
sjanptoms  are  misleading.  After  the  lameness  has  been  located 
in  a  certain  limb,  its  movement  must  be  carefully  noted  in  order 
to  detect  the  part  favored.  If  the  lameness  is  not  characteristic 
enough  to  enable  the  examiner  to  locate  the  seat  of  it,  it  is  then 
necessary  to  put  the  animal  through  some  movement  that  may 
emphasize  the  soreness  in  the  part.  The  animal  may  show  a  cer- 
tain reluctance  to  throw  weight  on  the  limb  when  turned  to  the 
right  or  left.  Moving  the  horse  in  a  small  circle  with  the  lame 
limb  on  the  outside  may  cause  the  animal  to  use  the  muscles 
of  the  shoulder  more  freely,  and  emphasize  any  soreness  that 
may  be  present.  If  the  lame  limb  is  on  the  inside,  soreness 
anywhere  in  the  foot  may  be  increased,  because  of  the  extra 
10 


146  NON-SPECIFIC  OR  GENERAL  DISEASES 

weight  tlirown  on  this  portion  of  the  limb.  Moving  the  animal 
over  a  hard  driveway  may  increase  the  pain  resulting  from  an 
inflammation  of  the  feet.  Causing  the  animal  to  trot  on  soft 
ground,  step  over  high  objects,  flexing,  extending,  abducting 
and  adducting  the  part  may  enable  the  examiner  to  locate  the 
exact  group  of  shoulder  or  arm  muscles  involved  by  the  disease. 
In  examining  the  feet  it  may  be  necessary  to  remove  the  shoes 
and  practise  percussion  and  pressure  over  the  region  of  the  sole. 
In  some  forms  of  lameness  it  may  be  necessary  to  destroy  the 
sensation  in  the  foot  by  injecting  cocaine  along  the  course  of  the 
nerves  that  supply  the  foot  before  arriving  at  a  definite  diagnosis. 

QUESTIONS 

1.  Define  the  term  unsoundness  and  give  an  example. 

2.  Define  the  term  blemish  and  give  an  example. 

3.  Give  the  general  method  of  examining  a  horse  for  soundness. 


CHAPTER  XVI 


DISEASES   OF  THE   FORE-LIMB 

Sprains  and  Injuries  in  the  Region  of  the  Shoulder. — 
Sprains  and  injuries  of  the  structures  in  the  shoulder  region  are 
more  common  in  horses  that  are  called  on  to  do  heavy  work  than 
among  driving  horses. 

The  following  causes  may  he  mentioned:  Ill-fitting  collars, 
pulling  heavy  loads  over  uneven  streets  or  soft  ground,  where  the 
footing  is  not  secure,  and  slipping  are  common  causes.  Young- 
horses  that  do  not 
know  how  to  pull,  or 
horses  that  are  tired 
out  by  hard  work, 
are  predisposed  to 
muscular  strain,  and 
are  apt  to  suffer  in- 
jury if  forced  to  do 
heavy  work.  Sore 
shoulders,  or  an  ig- 
norant driver,  may 
cause  the  animal  to 
pull   awkwardly  and 

throw  more  strain  on  Fig.  31.— shoulder  lameness. 

certain  groups  of  muscles  than  they  can  stand.  Eheumatism 
frequently  causes  shoulder  lameness.  The  muscle  usually 
affected  by  rheumatism  is  the  large  muscle  extending  from  the 
region  of  the  point  of  the  shoulder  to  the  summit  of  the  head. 

The  symptoms  of  shoulder  lameness  vary  in  the  different 
cases.  The  horse  may  walk  without  going  lame,  but  when  made 
to  trot  lameness  is  quite  noticeable.  The  animal  may  point  with 
the  foot  of  the  diseased  limb,  holding  it  forward,  but  squarely 

147 


148  NON-SPECIFIC  OR  GENERAL  DISEASES 

on  the  floor.  In  severe  strain,  little  weight  is  thrown  on  the 
limb  and  the  lameness  is  marked  (Fig.  31).  In  '^  shoulder  slip  " 
the  head  of  the  arm  bone  pushes  outward  every  time  the  animal 
throws  weight  on  the  limb.  This  luxation  can  be  noticed  best 
when  standing  in  front  of  the  animal.  Marked  atrophy  of  the 
external  shoulder  muscles  may  occur.  Such  atrophy  may  appear 
and  disappear  quickly,  and  may  result  from  an  injury  to  the 
nerve  supply  of  the  muscle  as  well  as  from  favoring  the  part. 
Atrophy  of  the  shoulder  may  occur  if  the  animal  is  lame  in  other 
regions  of  the  limb,  especially  the  feet.  The  outcome  of  shoulder 
lameness  is  favorable  if  the  disease  causing  it  is  given  prompt 
treatment. 

Eest  is  a  very  important  part  of  the  treatment.  It  may  be 
advisable  to  restrict  the  horse's  movements  by  placing  it  in  a 
single  stall,  and  tying  the  animal  so  that  it  can  not  lie  down. 
This  should  be  continued  for  at  least  one  week.  If  the  horse  is 
restless,  it  should  be  given  a  box-stall  or  turned  out  in  a  small 
lot  alone.  It  should  be  watered  and  fed  in  the  quarters  where 
confined.  The  local  treatment  consists  in  applying  mild  lini- 
ments or  blisters  to  the  shoulder.  It  is  not  advisable,  however, 
to  apply  a  blister  if  the  muscles  feel  hot  and  tender. 

Capped  Elbow,  "  Shoe-boil." — Capped  elbow  is  an  inflam- 
mation of  the  bursa  at  the  posterior  surface  of  the  elbow  (Fig. 
32).  The  swelling  that  results  is  usually  sharply  defined.  It 
may  feel  abnormally  warm  and  doughy,  and  it  may  be  painful. 
Later,  the  enlargement  may  be  well  defined  and  hard.  Some- 
times the  skin  is  indurated  and  lies  in  folds,  or  the  shoe-boil 
shows  abrasions  on  its  surface  and  fistulous  openings  leading 
from  abscess  centres.  The  cystic  or  soft  tumor  is  a  common 
form.  Such  an  enlargement  fluctuates  on  pressure,  and  when 
opened,  a  blood-stained  fluid  escapes.  All  forms  of  capped  elbow 
tend  to  become  chronic. 

The  treatment  is  both  preventive  and  local.  As  capped  elbow 
is  caused  by  bruising  the  part  with  the  hoof  or  heel  of  the  shoe, 


DISEASES  OF  THE  FORE-LIMB 


149 


the  preventive  treatment  consists  in  hindering  the  animal  from 
taking  a  position  that  may  favor  injnrv  to  the  part.  Confining 
the  animal  in  a  small  stall  and  tying  it  with  too  short  a  halter 
strap  favors  a  sternal  position  when  lying  dowm.  A  roomy  stall 
that  pennits  the  animal  to  stretch  or  change  position  is  an  im- 
portant preventive  measure.    Shoes  that  project  beyond  the  qnar- 


FiG.  32.— Shoe-boil. 

ters  shonld  be  avoided.     The  elbow  may  be  protected  by  placing 
a  thick  pad  over  the  heels  when  the  animal  is  in  the  stable. 

Local  treatment  varies  according  to  the  character  of  the 
enlargement.  Soft,  doughy  swellings  may  be  treated  by  aj^pli- 
cation  of  cold,  iodine  and  blisters.  The  cystic  form  of  tumor 
must  be  opened,  the  fluid  removed  and  the  lining  membrane 
destroyed  by  the  injection  of  tincture  of  iodine.    Hard,  indurated 


150  NON-SPECIFIC  OR  GENERAL  DISEASES 

shoe-boils  may  be  treated  bv  completely  removing  the  diseased 
tissue.  The  surgical  treatment  of  capped  elbow  requires  the 
service  of  an  exj^erienced  veterinarian.  His  efforts  may  prove 
a  complete  failure,  unless  the  irritation  to  the  part  by  the  shoe  or 
hoof  is  prevented. 

Injuries  to  the  Knee  (Broken  Knee). — Horses  frequently 
fall  and  bruise  or  lacerate  the  knee  when  moving  at  trot  or  canter. 
The  injury  varies  according  to  the  force  of  the  fall,  and  the 
character  of  the  road  that  the  animal  is  travelling  over.  Some 
individuals  are  more  liable  to  suffer  from  this  class  of  injuries 
than  others.  Horses  that  are  weak-kneed  because  of  poor  con- 
formation, or  knee-sprung,  are  inclined  to  stumble.  Careless 
driving,  especially  if  the  animal  is  tired,  predisposes  it  to  this 
class  of  injury.  Because  of  the  predisposition  toward  stumbling 
on  the  part  of  some  horses,  scars  on  the  front  of  the  knee  are 
termed  broken  knee,  and  the  animal  is  considered  unsound. 

The  symptoms  vary  with  the  extent  of  the  injury.  Slight 
bruises  or  abrasions  result  in  local  swelling  and  soreness  that  dis- 
appear within  a  few  days.  Laceration  of  skin  interferes  with 
the  movement  of  the  knee  and  the  animal  may  be  quite  lame. 
The  part  becomes  swollen  and  painful.  In  injuries  involving  the 
sheaths  of  the  tendons  and  the  synovial  membrane,  the  pain  is 
severe  and  the  accompanying  inflammation  may  take  on  a  serious 
form. 

The  preventive  treatment  should  not  be  overlooked.  Horses 
should  be  trained  to  carry  the  head  at  a  proper  height  when 
moving.  The  driver  should  handle  the  reins  properly  and  keep 
his  attention  on  the  horse  or  horses  that  he  is  driving.  Super- 
ficial bruises  require  no  special  treatment  other  than  rest.  Lacer- 
ation of  the  skin  and  underlying  tissue  requires  complete  rest 
and  careful  removal  of  any  particles  of  dirt  and  gravel  that  may 
be  present  in  the  wound.  Shreds  of  tissue  that  may  take  no  part 
in  the  healing  should  be  cut  away.  The  hair  in  the  region  of  the 
wound  should  be  trimmed  short.    Careful  and  repeated  dressings 


DISEASES  OF  THE  FORE-LIMB  151 

with  antiseptics  are  necessary  until  the  inflammation  has  largely 
disappeared  and  healing  is  rapidly  taking  place.  It  may  be 
advisable  to  tie  the  horse  in  the  stall  so  that  it  can  not  lie  down. 

Distended  Synovial  Sacs,  Joint  Sheaths  and  Bursae, 
"  Galls." — Soft  enlargements  may  occur  in  the  region  of  the 
knee  and  fetlock.  They  are  commonly  termed  "  galls,"  "  wind- 
galls,"  or  "  road-puffs."  They  are  usually  due  to  the  sheaths 
surrounding  the  tendons  becoming  distended  with  synovia. 
"  Galls  "  are  caused  by  strains,  direct  injury  to  the  part  and 
severe,  continuous  work.  Certain  individuals  may  develop  this 
class  of  blemishes  without  being  subject  to  any  unusual  con- 
ditions.    This  condition  is  seldom  accompanied  by  lameness. 

The  treatment  may  vary  in  the  different  cases.  If  the  dis- 
tended sheath,  or  bursal  enlargement,  is  caused  by  a  direct  injury 
or  strain,  cold  bandages  should  be  applied  and  the  part  given 
as  complete  rest  as  possible.  "  Wind-galls  "  may  be  removed  by 
a  surgical  operation.  It  is  not  advisable  to  attempt  the  removal 
of  "  road-puffs."  Eest,  stimulating  leg  washes  and  bandages 
may  temporarily  remove  the  latter. 

Sprung  Knees  (Buck  Knees). — This  condition  of  the  knee 
is  characterized  by  the  partly  flexed  condition  of  the  region.  It 
is  best  observed  by  standing  to  one  side  of  the  horse  (Fig.  33). 
Instead  of  the  forearm  and  cannon  regions  appearing  perpendicu- 
lar or  in  line,  they  are  directed  forward.  This  condition  may 
exist  in  varying  degrees.  Some  individuals  show  it  to  a  slight 
degree,  the  condition  being  accompanied  by  a  weakness  or  shaki- 
ness  of  the  knee  when  standing  at  rest.  Sometimes,  but  one  knee 
is  involved. 

The  causes  of  this  unsoundness  are  hereditary  and  accidental. 
Weak  knees  due  to  faulty  conformation  seldom  escape  becoming 
sprung  in  animals  that  are  given  hard  work.  Severe  and  con- 
tinuous driving  is  a  common  factor  in  the  production  of  this 
condition.  Strains  of  the  flexor  muscles  of  the  region  may  cause 
it.     The  retraction  of  the  flexor  muscles  and  their  tendons  and 


152 


NON-SPECIFIC  OK  GENERAL  DISEASES 


the  aponeurosis  of  the  antibraehial  region  occurs  in  this  disorder 
and  prevents  the  animal  from  extending  the  knee. 

The  region  is  greatly  weakened  by  this  condition  and  the 
animal  may  be  nntitted  for  active  work.  For  this  reason  the 
value  of  the  animal  is  greatly  diminished/ 

Treat)}} ent  is  unsatisfactory.  The  preventive  treatment  con- 
sists in  not  breeding  animals  that  have  poorly  conformed  knees 


I'lC,   33. — Sprung  knees 


Fig.  34.— Splints. 


and  using  the  proper  judgment  in  working  young  horses  and 
when  driving  or  riding  horses.  Certain  cases  may  be  greatly 
benefited  by  sectioning  the  tendons  of  the  external  and  middle 
flexors  of  the  mctacarpi.  To  insure  a  successful  outcome  in  any 
case  that  is  operated  on,  a  long  period  of  rest  is  required. 

Splints. — A  splint  is  a  bony  enlargement  situated  along  the 
line  of  articulation  between  the  splint  and  cannon  bones  (Fig. 


DISEASES  OF  THE  FORE-LIMB  153 

34).  This  blemish  is  due  to  an  inflammation  of  the  periosteum. 
It  is  a  very  common  blemish  and  is  generally  located  along  the 
splint  bones  of  the  forefeet,  especially  the  internal  ones. 

Splints  are  caused  by  strains  and  rupture  of  the  ligament 
that  binds  the  splint  bone  to  the  cannon  bone.  The  result  is  an  in- 
flaimnation  of  the  periosteum.  Slipping,  or  an  unbalanced  con- 
dition of  the  foot,  may  cause  this  injury  by  distributing  the 
weight  unequally  on  the  splint  bones.  Faulty  action  and  bad 
shoeing  may  cause  the  horse  to  strike  and  bruise  the  region. 

Symptoms  of  lameness  are  not  always  present.  A  high  splint 
involving  the  articulation  between  the  lower  row  of  carpal,  splint 
and  cannon  bones  may  be  considered  an  unsoundness,  because  of 
the  persistent  character  of  the  lameness.  The  animal  may  show 
little  or  no  lameness  when  walked,  but  if  moved  at  a  trot,  espe- 
cially over  a  hard  roadway,  it  may  show  marked  lameness.  The 
local  inflammation  is  characterized  by  a  small  swelling  lying 
along  the  splint  bone,  that  feels  hot  and  may  pit  on  pressure. 
After  a  time  the  inflammation  disappears  and  is  replaced  by  a 
hard,  bony  enlargement.  When  this  occurs  the  lameness  dis- 
appears. 

The  preventive  treatment  consists  in  keeping  the  feet  of 
young  horses  in  proper  balance  by  frequent  trimming  and  proper 
shoeing.  This  attention  is  very  necessary  in  young  colts  that 
are  running  in  pasture.  It  is  very  advisable  to  rest  the  animal 
during  the  period  of  inflammation.  Cold  bandages  should  be 
applied.  As  soon  as  the  inflammation  has  subsided  mild  counter- 
irritants  and  absorbents  may  be  used.  In  case  the  lameness 
persists,  more  severe  counterirritation  is  indicated. 

Inflammation  of  the  Flexor  Tendons  of  the  Digit. — The 
large  tendons  posterior  to  the  foot  and  the  suspensory  ligament 
that  separates  them  from  the  cannon  bone  frequently  become 
inflamed.  Sometimes  complete  rupture  of  one  or  more  of  these 
structures  occurs.  The  lighter  breeds  of  horses  are  the  most 
frequent  sufferers.     Because  of  the  greater  strain  thrown  on 


154  NON-SPECIFIC  OR  GENERAL  DISEASES 

the  tendons  of  the  forefeet,  inHammation  of  these  tendons  is 
far  more  common  than  it  is  in  the  hindfoot.  Diseased  conditions 
of  the  hind  tendons  are  nsually  dne  to  other  causes  than  strain. 

The  following  predisposing  and  accidental  causes  should  be 
considered:  Weak  flexor-tendons  and  heavy  bodies  predispose 
animals  to  inflammation  of  the  tendons  and  suspensory  ligament ; 
quality,  not  size,  is  the  factor  to  consider  when  judging  the 
strength  of  a  tendon ;  long,  slender  pasterns  increase  the  strain 
on  these  structures,  and  this  mechanical  strain  is  further  in- 
creased by  low  heels  and  long  toes ;  the  character  of  the  work  and 
the  condition  of  the  road  that  the  animal  travels  over  are  im- 
portant factors  to  consider ;  trotting  and  running  horses  more 
often  suffer  from  injuries  to  tendons  and  ligaments  than  draft 
horses ;  travelling  at  a  high  rate  of  speed  over  an  uneven  road, 
slipping  and  catching  the  foot  in  a  rut  or  car  track,  are  common 
causes ;  bruises  and  wounds  may  result  in  the  tendons  becoming 
inflamed ;  inflammation  of  the  tendinous  sheaths  and  tlie  tendons 
as  well  sometimes  occurs  in  influenza. 

Lameness  is  a  prominent  symptom.  The  pastern  is  held  in 
a  more  upright  position  than  normal,  ^\^len  the  animal  is  stand- 
ing, the  foot  is  rested  on  the  toe,  and  it  may  take  advantage  of 
any  uneven  place  on  which  to  rest  the  heel.  In  severe  strains  the 
local  symptoms  are  quite  prominent.  The  tendons  may  be  hot 
and  swollen.  Pressure  may  cause  the  animal  pain.  In  chronic 
tendinitis  the  tendon  may  be  thickened  and  rough  or  knotty. 
Pain  is  not  a  prominent  symptom  in  this  class  of  cases.  Shorten- 
ing of  the  inflamed  tendon  may  occur,  causing  the  animal  to 
knuckle  over.  Rupture  of  one  or  more  of  the  tendons  and  the 
suspensory  ligament  can  be  recognized  by  the  abnormal  exten- 
sion of  the  pastern.  If  the  ruptured  tendon  heals,  it  always 
results  in  a  thickening  at  the  point  of  the  rupture  that  gives  the 
tendons  a  bowed  appearance.     This  is  termed  bowed-tendon. 

The  lameness  resulting  from  an  inflammation  of  tendons 


DISEASES  OF  THE  FORE-LIMB  155 

resembles  that  resulting  from  strains  and  injuries  to  the  fetlock 
joint,  especially  in  the  region  of  the  sesamoid  hones. 

Inflammation  of  the  sesamoid  bones  differs  slightly  from  the 
former.  Pressure  over  the  posterior  region  of  the  fetlock  may 
cause  the  animal  pain.  The  lameness  shows  a  tendency  to  dis- 
appear with  rest  and  reappear  when  the  animal  is  again  worked. 
Lameness  is  most  prominent  in  some  cases  when  the  animal  is 
first  moved  out.  There  may  be  a  lack  of  local  symptoms,  such 
as  heat  and  swelling.  It  is  not  uncommon  for  a  bony  enlarge- 
ment to  form  on  the  sesamoid  bone  after  a  few  months  or  a  year. 

The  following  treatment  is  recommended.  Horses  that  have 
a  poor  quality  of  tendon  and  weak  fetlocks  and  pasterns  should 
not  be  used  for  breeding  purposes.  Careful  driving  would  pre- 
vent a  large  percentage  of  injuries  to  tendons.  The  most  im- 
portant treatment  for  all  injuries  due  to  strains  is  rest.  In  all 
cases  of  severe  strain  to  the  structures  in  this  region,  it  is  very 
advisable  to  apply  a  plaster  bandage.  This  should  be  left  on  for 
at  least  two  weeks.  When  the  acute  inflammation  has  subsided, 
counterirritants  may  be  applied.  Either  cold  or  hot  appli- 
cations are  recommended.  Cold  applications  are  to  be  preferred 
at  the  beginning  of  the  inflammation.  Covering  the  tendons  with 
a  cold  bandage,  or  with  a  heavy  layer  of  antiphlogistin,  is 
recommended.  The  horse  should  not  be  worked  until  after  the 
tendons  have  had  an  opportunity  to  completely  recover  from  the 
inflammation. 

Contracted  Tendons,  Knuckling-over. — jSTew-born  foals  are 
sometimes  unable  to  stand  on  their  front  feet  because  of  the 
excessive  knuckling-over.  The  colt  may  walk  on  the  front  of 
the  pastern  and  fetlock.  This  sometimes  results  in  severe  injury 
to  the  skin  and  the  underlying  tissues. 

Knuckling-over  in  the  mature  horse  is  not  always  due  to 
contracted  tendons.  It  may  occur  as  a  s^anptom  of  inflammation 
of  the  flexor  tendons,  ligaments  of  the  fetlock  joint  and  the 


156  NON-SPECIFIC  OR  GENERAL  DISEASES 

articulation  as  well.  It  may  be  noticed  in  animals  that  have 
ring-bone,  or  coffin-joint  lameness. 

The  most  common  cause  for  this  unsoundness  is  inflammation 
of  the  muscles  and  tendons  of  the  flexors  of  the  digit.  As  a 
result  of  long  standing  or  severe  inflammation,  shortening  of 
these  structures  occurs  in  consequence  of  the  contraction  of  the 
inflammatory  or  cicatricial  tissue.  Knuckling-over  in  the  new- 
born colt  is  commonly  caused  by  a  weakness  or  lack  of  innervation 
of  the  extensor  muscle  of  the  digit.  Judging  from  the  quick 
recovery  that  usually  occurs,  other  causes  for  this  condition 
are  seldom  present. 

The  treatment  recommended  for  the  new-born  colt  is  sup- 
porting the  fetlock  with  a  light  plaster  bandage.  This  should 
be  applied  very  soon  after  birth  in  order  to  prevent  bruising  of 
the  fetlock.  A  light  cheese-cloth  bandage  should  be  applied  to 
the  limb  from  the  hoof  to  the  knee.  The  colt  is  laid  on  its  side, 
the  toe  extended  as  much  as  possible,  and  the  plaster  bandage 
applied.  This  should  be  removed  in  about  one  week  and  fresh 
bandages  applied.  In  about  two  weeks  the  young  animal  is 
usually  able  to  walk  on  the  toe.  As  soon  as  it  is  able  to  do  this 
a  bandage  is  unnecessary.  It  is  not  advisable  to  turn  the  colt 
outside  if  there  is  any  chance  for  the  bandages  to  become  wet. 

Knuckling-over  due  to  faulty  conformation  is  difficult  to 
correct.  Light  work  and  careful  shoeing  are  the  most  valuable 
preventive  measures  in  young  horses.  Sprains  and  injuries  to 
the  region  of  the  fetlock  should  receive  the  necessary  treatment. 
The  treatment  for  contracted  tendon  is  largely  surgical  and  con- 
sists in  sectioning  it. 

Injuries  Caused  by  Interfering. — Horses  that  have  faulty 
action  may  strike  the  opposite  fetlock  with  the  moving  foot,  the 
inside  of  the  opposite  limb  in  the  region  of  the  knee,  and  the 
quarters  of  the  front  foot  with  the  shoe  of  the  hindfoot.  It  is 
very  common  for  horses  to  "  brush  "  the  inside  of  the  hind  fetlock 
with  the  opposite  foot  when  trotting,  especially  if  tired.     Inter- 


DISEASES  OF  THE  FORE-LIMB  157 

fering  in  the  front  feet  is  less  conmion.  Striking  the  inside  of 
the  region  of  the  knee  with  the  opposite  foot  or  "  speedy  cutting  " 
occurs  in  driving  and  speed  horses.  Both  of  the  latter  forms  of 
interfering  may  be  considered  unsoundnesses. 

The  most  common  cause  of  interfering  is  faulty  conforma- 
tion, such  as  narrowness  of  the  chest  or  pelvis,  faulty  confor- 
mation of  the  limbs  and  irregularity  in  the  action  of  the  joints. 
Shoeing  and  the  condition  of  the  feet  are  also  important  factors. 
Animals  that  have  a  narrow  chest  or  pelvis  interfere  because  the 
legs  are  placed  too  closely  together.  Turning  in  of  the  knees  or 
"  knock-kneed,"  winging  in  or  out  of  the  feet,  or  any  other- 
defective  conformation  of  the  limbs  that  tends  to  prevent  the 
animal  from  moving  the  feet  in  line,  lead  to  serious  interfering. 
A  wide-spreading  hoof,  an  unbalanced  condition  of  the  foot  and 
improper  fitting  of  the  shoes  are  common  causes  for  interfering 
in  horses  that  would  otherwise  move  the  feet  in  line.  Debility 
from  disease  and  overwork  may  cause  the  animal  to  interfere  tem- 
porarily. An  unbalanced  gait  and  shortness  of  the  body  are  the 
common  causes  for  injuries  to  the  quarters. 

All  degrees  of  injury  to  the  part  struck  by  the  shoe  or  wall 
of  the  foot  may  be  noted.  Horses  that  interfere  lightly,  wear 
the  hair  off  and  produce  slight  abrasions  of  the  skin  on  the  inside 
of  the  fetlock.  Sometimes  the  skin  is  bruised,  inflamed  or 
scarred.  Injuries  to  the  inside  of  the  knee  and  quarter  are  the 
most  serious.  Lameness,  inflammation  of  the  periosteum  and 
bony  enlargement  may  result  from  ^^  speedy  cutting."  Deep 
wounds  in  the  region  of  the  heel  or  quarter  may  occur  when  a 
horse  strikes  tliis  part  with  the  shoe  of  the  hindfoot  in  moving 
at  a  high  rate  of  speed. 

The  treatment  is  largely  preventive.  Xo  doubt  many  cases 
of  interfering  could  be  prevented  by  careful  training  and  balanc- 
ing of  the  foot  when  the  animal  is  growing  and  developing.  The 
feet  of  colts  should  be  trimmed  every  three  or  four  weeks.  Inter- 
fering in  the  hiudfeet  may  be  stopped  by  noting  the  character 


158 


NON-SPECIFIC  OR  GENERAL  DISEASES 


of  the  animal's  gait  and  the  portion  of  the  wall  that  strikes  the 
part,  and  by  practising  intelligent  methods  of  shoeing.  Slight 
injuries  should  be  treated  by  the  application  of  antiseptic  pow- 
ders. The  treatment  for  injuries  to  the  periosteum  is  the  same 
as  that  recommended  for  splints.  As  a  last  resort  boots  and 
button  rings  may  be  used  for  the  purpose  of  preventing  serious 
injury  to  that  part  which  is  struck  by  the  foot. 

„_  Ring-bone. — Chronic  in- 
flammation of  the  articula- 
tion between  the  first  and  sec- 
ond bones  of  the  digit  is 
temied  ring-bone  (Fig.  35). 
Not  all  ring-bones  involve  the 
articular  surfaces.  The  peri- 
articular, or  false  ring-bone,  is 
a  chronic  inflammation  of  the 
bone  near  the  articular  sur- 
face. The  bony  enlargement 
varies  in  size.  It  may  form  a 
ring  encircling  the  part,  or  it 
may  be  limited  to  the  lateral 
surface  of  the  joint.  The 
bony  enlargement  may  be  so 
small  as  to  be  detected  only 
by  a  careful  examination. 
Ring-bone  may  occur  on  any 
of  the  feet,  but  it  is  said  to  be  more  common  in  the  front  feet. 
The  predisposing  cause  of  ring-bone  is  faulty  conformation. 
Long,  weak  pasterns  that  are  predisposed  to  strains,  upright 
pasterns,  especially  if  small,  and  exposed  to  concussion  and  jar- 
ring, and  crooked  feet  that  distribute  the  weight  on  the  part 
irregularly  are  important  factors  in  the  production  of  ring-bones. 
The  external  causes  are  sprains  or  any  injury  to  the  region. 
Lameness  is  nearly  always  present.     The  degree  of  lameness 


Fig.  35. — (A)  Bones  of  digit,  showing  (C) 
side  bones,  and  (D)  ring-bones,  and  (B)  nor- 
mal bones  of  digit. 


DISEASES  OF  THE  FORE-LIMB  159 

varies,  and  does  not  depend  altogether  on  the  size  of  the  bony 
enlargement.  Large  ring-bones  interfere  with  the  movement  of 
the  tendon.  Lameness  is  most  pronounced  when  weight  is  thrown 
on  one  foot,  the  later  phase  of  the  step  being  shortened  and  the 
pastern  more  upright.  Some  cases  improve  with  rest,  but  the 
lameness  returns  when  the  animal  is  given  hard  work. 

The  preventive  treatment  consists  in  giving  the  necessary 
attention  to  the  feet  of  young  animals,  by  trimming  the  wall  fre- 
quently and  keeping  the  feet  in  balance  and  the  careful  selection 
of  breeding  stock.  Resting  the  animal,  keeping  the  foot  that  has 
the  ring-bone  on  it  in  proper  balance  and  counterirritation  by 
means  of  blisters  and  cautery  (searing)  are  important  lines  of 
treatment.  Shortening  the  toe  and  raising  the  heel,  if  necessary, 
greatly  relieves  the  lameness  in  some  cases.  Sectioning  the  sen- 
sorv  nerves  that  go  to  the  part  should  not  be  practised,  unless  in 
exceptional  cases. 

QUESTIONS 

1.  Give  the  causes  of  shoulder  lameness;  give  the  treatment. 

2.  Describe  capped  elbow;  give  the  treatment. 

3.  What  is  "  broken  knee  "  ? 

4.  What  are  "wind-galls"  and  "road-puffs"? 

5.  Give  the  cause  and  treatment  of  sprung-knee. 

6.  Give  the  cause  and  treatment  of  splints. 

7.  What  class  of  horses  most  commonly  have  strained  tendons?     Give  the 

causes  and  treatment  of  this  form  of  lameness. 

8.  Give  the  treatment  of  contracted  tendons  in  the  new-born  colt. 

9.  Give  the  causes  for  interfering. 

10.  \Miat  are  the  different  forms  of  ring-bone?     Give  the  causes  and  treat- 
ment of  ring-bone. 


CHAPTER  XVII 


DISEASES  OF  THE  FOOT 

General  Discussion. — The  foot  of  tlio  horse  as  generally 
spoken  of,  includes  the  hoof  and  the  structures  that  are  enclosed 
by  it  (Fig.  3G).  It  may  be  divided  into  three  parts,  the  insensi- 
tive and  sensitive  structures  and 
the  bony  core.  The  insensitive 
foot  or  hoof  is  divided  into  wall, 
sole,  frog  and  bars.  The  sensitive 
foot  is  divided  into  vascular  tissue 
and  elastic  apparatus.  The  vascu- 
lar tissue  is  in  turn  divided  into 
coronary  cushion,  lamina?  and  vel- 
vety tissue.  The  elastic  apparatus 
is  divided  into  plantar  cushion  and 
fibro-cartilages.  The  bony  core  is 
formed  by  the  navicular  and  third 
digital  bones.  The  hoof  and  vascu- 
lar tissue  in  tura  enclose  the 
elastic  apparatus  and  bony  core. 

The  wall  forms  that  portion 
of  the  hoof  seen  when  the  foot  rests 
on  the  ground  (Fig.  37).  It  is 
covered  by  a  thin  layer  of  hoiiiy 
tissue,  the  iieripole,  that  coats  over 
the  wall  and  assists  in  preventing 
its  drying  out.  On  lifting  the  foot 
and  examining  its  inferior  surface,  it  is  noticed  that  the  wall  at 
the  heels  is  inflected  under  the  foot  and  in  a  forward  direction. 
This  portion  of  the  wall  is  termed  the  hars.  Within  the  bearing 
margin  of  the  wall  and  in  front  of  the  bars  is  a  thick,  concave, 
horny  plate  that  forms  the  sole.  At  the  heels  and  betv/een  the 
160 


Fia.  36. — Photograph  of  a  model  of 
the  foot:  (D)  wall;  (F)  sensitive  tissue; 
(G)  plantar  cushion,  inferior  dark  por- 
tion, sole  and  frog;  (A)  lateral  carti- 
lage; and  (N)  pedal  bone. 


DISEASES  OF  THE  FOOT 


161 


bars  is  a  wedge-sliaped  mass  of  rather  soft  horny  tissue  that 
projects  forward  into  the  sole.  This  is  the  foot  jjad  or  horiiy 
frog.     It  is  divided  into  two  lateral  portions  by  a  medium  cleft. 

The  coronary  cushion  projects  into  the  upper  border  of 
the  wall.  It  is  covered  with  vascular  papillse  which  secrete  the 
horny  fibres  that  form  the  wall.  The  vascular  lamince  are  leaf- 
like projections,  the  sides  of  which  are  covered  by  secondary 
leaves.  Honu/  laminar,  arranged  the  same  as  vascular  laminar, 
line  the  wall.  These  tAvo 
structures  are  so  fir  m  1  y 
united  that  it  is  impossible 
to  tear  them  apart  without 
destroying  the  tissue.  The 
velvety  tissue  covers  all  of 
the  inferior  surface  of  the 
foot,  with  the  exception  of 
the  bars.  As  the  name  indi- 
cates, its  surface  is  covered 
liv  vascular  papillir  that  re- 
semble tlie  ply  on  velvet.  It 
is  firmly  united  to  the  horny 
sole  which  it  secretes. 

The  lateral  cartilages  are 
attached  to  the  posterior 
angles  of  the  pedal  bone.  They  are  flattened  from  side  to  side, 
and  the  portion  that  projects  above  the  coronary  cushion  may 
be  felt  by  pressing  on  the  skin  that  covers  it.  The  plantar 
cushion  is  a  wedge-shaped  piece  of  tissue  formed  by  interlacing 
connective-tissue  fibres  and  fat.  It  is  limited  on  each  side  by  the 
lateral  cartilages.    Its  inferior  face  is  moulded  to  the  frog. 

The  bony  core  formed  by  the  last  bone  of  the  digit  and  the 

coffin  bone  was  described  briefly  with  the  other  foot  bones.     A 

very  important  bursa,  because  it  is  so  frequently  inflamed  in 

coffin-joint  lameness,  facilitates  the  gliding  of  the  flexor  tendon 

11 


Fig.    37. 


-Foot    showing    neglect    in    trim- 
ming wall. 


162 


NON-SPECIFIC  OR  GENERAL  DISEASES 


over  the  navicular  bone  before  it  becomes  attached  to  the  inferior 
face  of  the  pedal  or  digital  bone. 

Side-bones, — This  is  a  chronic  inflammation  of  the  lateral 
cartilages  of  the  foot  that  results  in  their  ossification  (Fig.  38). 
This  unsoundness  is  common  in  heavy  horses,  especially  if 
worked  on  city  streets.  The  inflammation  affects  the  cartilages 
of  the  front  feet,  rarely  those  of  the  hindfeet. 

The  hereditary  tendency  toward  the  development  of  side- 
bones  is  an  important  predisposing  factor.     It  is  not  uncommon 


Pig.   38. — A  very  large  side  bone. 

to  meet  with  this  unsoundness  in  young  horses  that  have  never 
been  worked.  Low,  weak  heels,  flat,  spreading  feet,  or  any 
other  faulty  conformation  of  the  foot  are  predisposing  factors. 

The  character  of  the  work  is  an  important  exciting  cause. 
Continuous  work  over  paved  streets,  especially  if  the  horse  is 
shod  with  high-hooled  shoes,  increases  the  shock  received  by  the 
elastic  apparatus  of  the  foot.  This  produces  more  or  less  irri- 
tation to  the  lateral  cartilages,  which  may  result  in  their  com- 
plete ossification.  Punctured  wounds  in  the  regions  of  the  carti- 
lage may  cause  it  to  become  inflamed  and  changed  to  bone. 

The  following  symptoms  may  be  noted.     Farm  horses  that 


DISEASES  OF  THE  FOOT  163 

have  side-bones  seldom  show  lameness.  This  is  because  they 
are  worked  on  soft  ground  and  not  on  a  hard  street  or  road. 
Driving'  and  drny  horses  may  step  short  with  the  front  feet,  or 
show  a  stilty  action.  This  may  disappear  with  exercise.  The 
lameness  is  sometimes  marked.  The  local  diseased  changes  are 
the  greatest  help  in  the  recognition  of  side-bones.  Horses  should 
not  be  passed  as  sound  without  making  a  careful  examination  of 
the  lateral  cartilages.  This  examination  is  made  by  pressure 
over  the  region  of  the  cartilage  with  the  thumb  or  fingers.  This 
is  for  the  purpose  of  testing  its  elasticity.  If  it  feels  rigid 
and  rough,  the  cartilaginous  tissue  has  been  replaced  by  bony 
tissue,  and  the  animal  should  be  classed  as  unsound. 

The  treatment  is  largely  preventive.  Horses  with  side-bones 
should  not  be  bred.  It  is  not  advisable  to  use  horses  with  side- 
bones  on  the  road  or  city  streets.  Shoeing  with  riibber  pads  may 
help  in  overcoming  the  concussion  and  relieve  the  lameness. 
Sectioning  the  sensory  nerves  going  to  this  portion  of  the  foot  is 
advisable  in  driving  horses.  Rest  and  counterirritation  relieve 
the  lameness  for  a  short  time. 

Navicular  Disease. — In  navicular  disease  the  bursa,  flexor 
tendon,  and  navicular  bone  may  become  chronically  inflamed. 
Because  of  the  seat  of  the  lameness,  it  is  commonly  known  as 
"  coflin-joint "  lameness.  This  disease  affects  standard  and 
thoroughbred  horses  more  often  than  it  does  the  coarser  breeds. 
One  or  both  front  feet  may  be  affected  (Fig.  39). 

Hereditary  causes  are  largely  responsible  for  navicular  dis- 
ease. The  tendency  toward  this  disease  probably  depends  on 
such  peculiarities  of  conformation  as  narrow,  weak,  high  heels, 
long  pasterns  and  too  long  a  toe.  The  character  of  the  work  is 
an  important  factor.  Hurried,  rapid  movements  throw  consider- 
able strain  on  the  navicular  region,  increasing  the  danger  from 
injury.  This  is,  no  doubt,  one  reason  for  "  coffin-joint  "  lame- 
ness being  more  common  in  driving  and  speed  horses  than  in 
slow-going  work  animals.    Rheumatic  inflammation,  bad  shoeing 


164 


NON-SPECIFIC  OR  GENERAL  DISEASES 


and  punctured  wounds  in  the  region  of  the  bursa  many  cause  it. 
Tlie  /'irst  si/viptom  usually  noted  is  a  tendency  to  stumble. 
Wheu  standing  in  the  stable,  the  animal  "  points  "  or  rests  the 
diseased  foot.  Sometimes  it  rests  the  heel  of  the  lame  foot  on 
the  wall  of  the  opposite  foot.  If  both  feet  are  affected,  the  animal 
may  rest  them  alternately,  or  take  a  position  with  both  feet  well 


Fig.  39. — A  case  of  navicular  disease  involving  one  front  foot.     The  diseased  foot  is  the 

smaller. 

in  front  of  the  normal  position.  The  inflamed  structures  are  so 
covered  by  other  tissues  that  it  is  difficult  to  detect  the  local 
inflammation,  or  cause  the  animal  to  flinch  by  applying  pressure 
over  the  region.  As  the  disease  becomes  more  advanced,  the 
lameness  becomes  permanent.  The  limb  is  carried  forward 
stiffly  and  rapidly  and  the  animal  stumbles  when  travelling  over 
rough  ground.  In  time,  because  of  the  little  weight  thro^vn  on 
the  posterior  portion  of  the  foot,  the  quarters  may  become  higher, 


DISEASES  OF  THE  FOOT 


165 


contracted  and  more  iipriglit  and  the  frog  smaller.     If  one  foot 
is  diseased,  it  becomes  smaller  than  the  opposite  foot. 

The  following  preventive  measures  may  be  recommended. 
We  should  not  use  animals  having  faulty  conformation  of  the 
feet  for  breeding,  because  the  offspring  of  such  individuals 
have  an  inherent  tendency  toward  navicular  and  other  foot  dis- 
eases.    Animals  that  have  '"  cofHn-joint  "'  lameness  should  be 


Fig.  40. — An  improperly  shod  foot ;  note  the  manner  in  whicli  the  wall  is  cut  awaj  at  the  toe 

allowed  to  run  in  pasture  as  much  as  possible,  because  natural 
conditions  help  to  keep  down  the  inflammation  and  soreness  and 
promote  a  more  healthy  condition  of  the  foot.  In  shoeing  the 
horse  it  is  best  to  shorten  the  toe  and  raise  the  heel.  It  is  advisa- 
ble in  the  more  favorable  cases  to  cut  the  sensory  nerves  of  the 
foot.  This  operation  destroys  the  sensation  in  the  foot,  and 
should  not  be  performed  on  feet  with  weak  heels,  or  that  are 
wide  or  spreading. 

Contracted  Quarters. — This  condition  of  the  feet  is  charae- 


IGG  NON-SPECIFIC  OR  GENERAL  DISEASES 

terizcd  by  the  foot  becoming'  narrow  in  its  posterior  portion.  One 
or  both  of  the  quarters  may  be  affected.  It  is  principally 
observed  in  the  forefeet. 

The  causes  of  contraction  of  the  foot  may  be  classed  as 
predisposing,  secondary  and  exciting.  It  may  accompany  chronic 
diseases  of  the  foot,  snch  as  navicular  disease  and  side-bones. 
Weak  heels  is  the  principal  predisposing  factor.  Any  condition 
that  tends  to  prevent  the  hoof  from_  taking  up  moisture,  or  causes 
it  to  lose  moisture,  may  cause  the  horn  to  lose  flexibility  and 
contract.  This  is  one  of  the  reasons  why  horses  that  are  worked 
continuously  in  cities,  or  used  for  driving,  frequently  develop 
contracted  feet.  Ill-fitting  shoes,  excessive  rasping  of  the  wall 
and  bars,  and  allowing  the  shoes  to  stay  on  the  foot  for  too  long 
a  time  are  responsible  to  a  very  large  degree  for  this  disorder 
of  the  foot  (Fig.  40). 

The  following  local  symptoms  may  occur:  The  wall  of  the 
foot  at  the  quarters  may  ajipear  drawn  in  at  its  superior  or 
inferior  portion.  Sometimes  one  or  both  quarters  are  perpen- 
dicular, or  nearly  so.  The  foot  then  appears  too  narrow  at  the 
heel,  too  elongated  and  less  rounded  than  normal.  The  changes 
in  the  appearance  of  the  inferior  surface  of  the  hoof  vary. 
The  changes  here  may  be  so  slight  that  they  are  not  noticed. 
In  well  advanced  and  neglected  cases  the  arch  of  the  sole  is 
increased,  the  frog  is  narrow  and  atroj)hied  and  the  bars  high 
and  perpendicular.  Corns  may  accompany  the  contraction. 
The  foot  may  feel  feverish.  The  animal  may  manifest  the  pain 
in  the  feet  when  standing  at  rest  by  pointing  and  changing  their 
position,  ^^^len  lameness  is  present,  it  may  resemble  that  occur- 
ring in  inilammation  of  lateral  cartilages  and  navicular  disease. 

Frcvenlivc  treatment  is  of  the  greatest  importance.  This 
consists  in  giving  the  feet  an  opportunity  to  take  up  moisture 
when  they  are  exposed  to  abnormal  conditions  and  become  fever- 
ish. Under  such  conditions,  it  is  advisable  to  occasionally 
remove  the  shoes  and  turn  the  animal  into  a  pasture  or  lot.      It 


DISEASES  OF  THE  FOOT  167 

is  best  to  do  this  in  the  fall  or  winter  when  the  ground  is  wet. 
If  this  can  not  be  practised,  the  shoes  should  be  removed  and 
a  poultice  of  ground  flaxseed  and  bran,  equal  parts,  applied  to 
the  feet  for  a  period  of  eight  or  ten  hours,  daily  for  a  week 
or  two.  A  plank  trough  six  inches  deep,  two  feet  wide  and  as 
long  as  the  stall  is  wide  may  be  filled  with  a  stiff  clay,  and  the 
horse  made  to  stand  with  its  front  feet  in  the  clay  bath  for  ten 
or  twelve  hours  daily.  When  grooming  the  horse,  the  foot  should 
be  cleaned  with  a  foot-hook  and  washed  with  clean  water.  Hoof 
ointments  should  be  avoided  so  far  as  possible.  The  importance 
of  fitting  the  shoe  to  the  foot,  avoiding  the  too  free  use  of  the 
rasp  and  hoof  knife  and  resetting  or  changing  the  shoe  when 
necessary  can  not  be  overestimated.  Shoeing  the  animal  with  a 
special  shoe  is  sometimes  necessary.  It  is  not  advisable  to 
attempt  the  forcible  expansion  of  the  quarters.  Lowering  the 
heels  by  careful  trimming  of  the  wall  and  sole  and  permitting 
frog  pressure  may  be  all  the  special  attention  required. 

Sand-crack. — A  fissure  in  the  wall  of  the  foot  running  in  the 
same  direction  as  the  horny  fibres,  or  a  seam  in  the  wall  resulting 
from  the  healing  of  the  fissure  is  termed  sand-crack.  The  posi- 
tion and  extent  of  the  fissure  or  seam  vary.  It  may  involve 
the  wall  of  the  toe  (toe-crack)  (Fig.  41)  or  quarter  (quarter- 
crack)  (Fig.  42).  It  is  superficial  or  deep,  according  to  the 
thickness  of  the  wall  involved;  complete  or  inco))iplete,  depend- 
ing on  wdiether  it  extends  from  the  bearing  margin  of  the  wall 
to  the  coronary  band  or  only  a  portion  of  the  distance ;  simple, 
when  the  horny  tissue  only  is  involved ;  and  complicated,  when 
the  sensitive  tissue  beneath  becomes  injured  and  inflamed. 
Cracks  of  long  standing  usually  have  thick,  rough  margins. 

The  causes  of  this  unsoundness  are  poor  quality  of  horn, 
improper  care  and  injuries.  Sand-cracks  commonly  occur  in 
hoofs  that  are  dry  arid  brittle  and  liave  thin  walls.  In  young 
horses  incomplete  cracks  due  to  the  wall  becoming  long  and 
breaking  off  in  large  pieces  are  common.     Unequal  distribution 


1G8 


NON-SPECIFIC  OR  GENERAL  DISEASES 


of  weight,  the  result  of  unskilled  shoeing,  or  any  other  condition 
that  may  cause  the  foot  to  become  unbalanced,  using  the  foot 
rasp  too  freely,  and  such  diseases  as  quitter,  corns  and  con- 
tracted quarters  subject  the  animal  to  this  form  of  unsoundness. 
Any  injury  to  the  coronary  cushion  that  secretes  the  fibres  of  the 
horny  wall  may  result  in  either  toe-  or  quarter-crack.  Treads  and 
barb-wire  cuts  are  common  injuries  to  the  region  of  the  coronet. 
The  preventive  treatment  consists  in  preserving  a  healthy 
condition  of  the  horn  by  giving  the  foot  the  necessary  care  and 
attention  in  the  way  of  proper  trimming  and  shoeing,  and  pro- 


FlG.   41. — (A)   Toc-craoks. 


Fig.    42.— Quarter-rr?ck  caused  by  barb- 
wire  cut. 


viding  it  with  the  necessary  moisture  by  means  of  foot-baths, 
wet  clay  and  poultices.  Quarter-cracks  respond  to  treatment 
more  quickly  than  toe-cracks.  The  treatment  is  practically  the 
same  for  both.  This  consists  in  preventing  motion  in  the  margins 
of  the  fissure  so  far  as  possible. 

The  treatme7it  for  fissures  in  the  region  of  the  toe  and  quarter 
is  as  follows:  The  wall  should  be  cut  away  along  the  margins 
of  the  crack  until  it  is  quite  thin;  and  extra  nail  holes  should 
1)0  made  in  the  shoe,  and  a  nail  driven  into  the  bearing  margin 
of  the  wall  a  little  to  each  side  of  the  fissure.  The  wall  at  the 
toe  should  be  shortened  and  the  toe  of  the  shoe  rolled  if  the 
animal's  work  permits  the  use  of  this  kind  of  a  shoe. 


DISEASES  OF  THE  FOOT  169 

The  margins  of  a  quarter-crack  and  the  wall  just  posterior 
and  below  it  should  be  cut  away  until  (iuite  thin.  The  bearing 
margin  should  then  be  trimmed  so  that  it  does  not  rest  on  the 
shoe.  A  bar  shoe  that  does  not  press  on  the  frog  may  be  used. 
Light  blisters  to  the  region  of  the  coronet  help  in  stimulating 
the  growth  of  the  horn.     Rest  is  advisable. 

Corns. — This  term  is  applied  to  injuries  to  the  foot  caused 
by  bruises  or  continuous  pressure  to  the  posterior  portion  of  the 
sole.     This  condition  is  common  in  the  forefeet. 

The  predisposing  causes  are  faulty  conformation  that  favors 
pressure  from  the  shoe  on  the  sole  between  the  bars  and  wall  and 
weak  heels.  Corns  are  commonly  met  with  in  feet  having  con- 
tracted quarters.  The  principal  exienml  causes  are  wrong 
methods  of  shoeing  and  allowing  the  shoes  to  remain  on  the  feet 
for  too  long  a  period. 

A  common  sympdom  of  corns  is  lameness.  In  order  to  relieve 
the  pressure  over  the  inflamed  part,  the  animal  stands  with  the 
foot  slightly  flexed  at  the  fetlock.  The  lameness  is  not  charac- 
teristic. It  is  only  by  a  local  examination  of  the  foot,  made 
by  pressing  on  the  sole  or  cutting  away  the  horn,  that  we  are 
able  to  form  a  positive  diagnosis. 

We  describe  the  diseased  changes  by  using  the  terms  dry, 
moist  and  suppurative  corns.  In  the  dry  corn  we  find  the  horn 
stained  and  infiltrated  with  blood.  In  the  moist  corn  the  hoof 
may  be  colored  the  same  as  in  the  former,  but  in  addition  there 
is  a  space  between  the  vascular  and  horny  tissue  that  is  filled 
with  a  serous-like  fluid.  If  this  collection  of  fluid  becomes  in- 
fected with  pus  organisms  and  is  changed  to  pus.  it  is  then 
termed  a  suppurative  corn.  Sometimes  the  pus  pushes  its  way 
upward  and  backward  between  the  sensitive  lamina;  and  the 
wall,  and  makes  its  appearance  at  the  margin  of  the  coronary 
band  in  the  region  of  the  quarters  or  heels.  This  usually  occurs 
when  the  tissues  beneath  the  horny  frog  become  bruised  or  the 
sensitive  tissue  pricked  by  a  nail.      It   is  commonly   termed 


170  NON-SPECIFIC  OR  GENERAL  DISEASES 

"  gravelled."  Pus  rarely  breaks  through  the  thick  horny  tissue, 
but  follows  the  wall  and  breaks  through  the  skin  where  it  meets 
with  the  least  resistance.  Corns  may  be  considered  a  serious 
unsoundness  in  driving  horses. 

The  treatment  is  largely  preventive.  Trimming  the  foot 
and  fitting  the  shoe  properly  are  important  preventive  measures. 
The  practice  of  cutting  away  the  bars  and  sole  or  ''  opening  up 
the  heels,"  as  it  is  commonly  termed,  should  be  condemned. 
This  method  of  trimming  the  foot  instead  of  preventing  corns 
is  a  vei'v  common  factor  in  producing  them.  The  shoe  should 
not  be  too  short  or  too  narrow.  It  should  follow  the  outline  of  the 
wall  and  rest  evenly  on  its  bearing  margin.  If  this  is  practised, 
weakening  the  wall  by  cutting  off  that  portion  allowed  to  project 
beyond  the  shoe  is  unnecessary.  Feet  that  have  low  heels  and 
large,  prominent  frogs  should  be  shod  with  shoes  thick  at  the 
heels.  The  best  line  of  treatment  for  a  horse  that  is  subject  to 
corns  is  to  remove  the  shoes  and  allow  the  animal  to  run  in  a 
pasture.  If  this  is  impossible,  poulticing  the  feet  or  standing 
the  animal  in  moist  clay  will  help  in  relieving  the  soreness. 
Excessive  cutting  away  of  the  horny  sole  is  contra-indicated.  Sup- 
purative corns  should  be  given  proper  drainage  and  treatment. 

Laminitis,  "  Founder." — This  is  an  inflammation  of  the 
sensitive  or  vascular  stricture  of  the  foot.  The  inflammation 
may  be  acute,  subacute  or  chronic.  Stockmen  frequently  use  a 
classification  for  laminitis  based  on  the  causes.  Feed,  road  and 
water  founder  are  common  terms  used  in  speaking  of  this  dis- 
ease.    The  inflanmuition  is  usually  limited  to  the  front  feet. 

The  causes  of  laminitis  are  overfeeding,  sudden  changes  in 
the  feed,  drinking  a  large  quantity  of  water  when  the  animal  is 
overheated,  overexertion,  exliaustion  and  chilling  of  the  body  by 
standing  the  animal  in  a  cold  draft.  It  may  be  associated 
with  such  diseases  as  rheumatism,  influenza  and  colic. 

The  symptoms  vary  in  the  different  forms  of  the  disease. 
Pain  is  the  most  characteristic  symptom.     The  sensitive  or  vas- 


DISEASES  OF  THE  FOOT  171 

ciilar  structure  of  the  foot  has  an  abundant  supply  of  sensory 
nerves,  and,  as  it  is  situated  between  the  hoof  and  the  bony  core, 
the  pressure  and  pain  resulting  from  the  inflammation  are  severe. 
In  the  acute  form  general  symptoms  are  manifested.  The 
appetite  is  impaired,  the  body  temperature  elevated  and  the  pulse 
beats  and  respirations  quickened.  If  the  inflammation  is  severe, 
the  animal  prefers  to  lie  down.  This  is  especially  true  if  all  four 
feet  are  inflamed.  In  most  cases  the  horse  stands  with  the 
forefeet  well  forward  and  the  hind  feet  in  front  of  their  normal 
position  and  under  the  body.  The  affected  feet  are  feverish  and 
very  sensitive  to  jarring  or  pressure.  Moving  about  increases 
the  pain  in  the  feet,  and  it  may  be  very  difiicult  to  make  the 
animal  step  about  the  stall. 

In  the  subacute  form  the  symptoms  are  less  severe.  The 
irregularity  in  the  gait  is  especially  noticeable  when  the  animal 
is  turned  quickly.  The  local  symptoms  are  less  marked  than 
in  the  acute  form  and  the  general  symptoms  may  be  absent. 

The  chronic  form  is  characterized  by  changes  in  the  shape 
and  appearance  of  the  liDofs  (Fig.  43).  The  wall  shows  prom- 
inent ridges  or  rings,  the  toe  may  be  concave,  thick  and  long  and 
the  sole  less  arched  than  usual,  or  convex.  The  degree  of  lame- 
ness varies.  It  is  more  noticeable  when  the  horse  is  moved  over 
a  hard  roadway  than  if  moved  over  soft  ground.  One  attack  of 
laminitis  may  predispose  the  aninnil  to  a  second  attack. 

The  jjrognosis  depends  on  the  character  of  the  inflammation 
and  the  promptness  and  thoroughness  of  the  treatment.  Acute 
laminitis  may  respond  to  prompt,  careful  treatment  in  from 
ten  to  fourteen  days.  Subacute  laminitis  responds  readily  to 
treatment.    The  prognosis  is  least  favorable  in  the  chronic  form. 

The  preventive  treatment  is  very  important.  Dietetic  causes 
are  responsible  for  a  large  percentage  of  the  cases  of  this  disease. 
Horses  that  are  accustomed  to  being  fed  and  watered  at  irregular 
periods  and  after  severe  or  unusual  exercise  seem  to  be  able  to 
stand  this  treatment  better  than  animals  that  are  more  carefully 


172 


NON-SPECIFIC  OR  GENERAL  DISEASES 


cared  for,  but  even  this  class  of  animals  do  not  always  escape 
injnry.  Stockmen  should  realize  the  danger  of  producing  an 
inflammation  of  the  feet  by  feeding  grain  and  giving  cold  water 
to  horses  immediately  after  severe  exercise.  Overfeeding  should 
also  be  avoided.  Careful  nursing  may  prevent  the  occurrence  of 
laminitis  as  a  complication  of  other  diseases. 


i 

\     "'^"^M 

1 

! 

•*    .   -^ 

i 
1 

ML  ^ 

in 

_,  f.-a*:a 

1                 n' 

1 

,     ,*^; 

"     --v^^^li 

Fio.  43. — This  foot  shows  the  changes  in  shape  and  appearance  of  wall  and  sole  occurring 

in  chronic  laminitis. 

The  ireatmeiit  of  the  inflammation  is  as  follows :  The  removal 
of  the  shoes  and  the  necessary  trimming  of  the  foot  should  be 
practised  early  in  the  inflammation ;  the  horse  should  be  placed 
in  a  roomy  box-stall  that  is  well  bedded  with  cut  straw ;  during 
the  cool  weather  it  may  be  necessary  to  blanket  the  animal; 
if  the  weather  is  hot  and  the  flies  annoy  the  patient,  the  stall 


DISEASES  OF  THE  FOOT  173 

should  be  darkened;  in  serious  cases,  and  when  the  animal  is 
heavy,  it  nnay  be  advisable  to  use  a  sling-;  hot  water  fomentations 
are  to  be  preferred;  the  patient  may  be  stood  in  a  tub  of  hot 
watei\  or  heavy  woollen  bandages  that  have  been  dipped  in  hot 
water  and  wrung  out  as  dry  as  possible  may  be  applied  to  the 
feet ;  the  temperature  of  the  water  should  be  no  hotter  than 
can  be  comfortably  borne  with  the  hands ;  the  results  of  this  treat- 
ment depend  on  the  faithfulness  with  which  it  is  carried  out; 
a  poultice  of  ground  flaxseed  should  be  applied  to  the  foot  at 
night,  or  during  the  interval  between  the  foot-baths.  This  treat- 
ment may  be  continued  until  the  acute  inflammation  has  subsided. 

If  the  animal  is  inclined  to  eat,  it  should  be  fed  very  little 
roughness  and  grain.  Soft  feeds  are  to  be  preferred,  and  ojie 
quart  of  linseed  oil  given  as  a  physic.  After  a  period  of  from 
ten  days  to  three  weeks,  depending  on  the  tenderness  of  the  feet, 
the  wall  at  the  toe  should  be  shortened,  the  sole  trimmed  if 
necessary,  flat  shoes  rolled  at  the  toe  placed  on  the  feet,  and 
the  animal  allow^ed  to  exercise  a  short  time  each  day  in  a  lot  or 
pasture.  As  the  hoof  growls  rapidly,  it  is  necessary  to  trim  it 
carefully  every  three  or  four  weeks  and  replace  the  shoes.  The 
wall  at  the  toe  should  be  kept  short,  but  excessive  thinning  of  the 
sole  should  be  avoided. 

The  same  line  of  treatment  as  recommended  for  the  horse 
may  be  used  for  laminitis  in  cattle.  If  marked  diseased  changes 
occur  in  the  feet,  it  is  not  advisable  to  attempt  the  treatment 
of  chronic  laminitis,  unless  it  is  in  valuable  breeding  animals. 

QUESTIONS 

1.  Give  a  general  description  of  the  foot. 

2.  State  the  nature  and  causes  of  side-bones. 

3.  What  are  the  causes  of  navicular  disease?    Give  symptoms  and  treatment. 

4.  \Miat  are  corns?     Give  the  treatment. 

5.  Give  the  nature  and  treatment  of  quarter-  and  toe-cracks. 

6.  Give  the  symptoms  and  causes  of  laminitis. 

7.  Give  lines  of  treatment  to  be  followed  in  the  different  forms  of  laminitis. 

8.  How  may  laminitis  be  prevented  ? 


CHAPTER  XVIII 
DISEASES  OF  THE  HIND  LIMB 

Fracture  of  the  Ileum,  "  Hipped." — Fracture  of  the  angle 
and  neck  of  the  ileum  may  be  chissed  among  the  common  fractures 
in  horses  and  cattle.  Fractures  involving  other  parts  of  the 
pelvic  bones  are  less  common.  Such  fractures  are  due  to  acci- 
dental causes,  as  striking  the  point  of  the  hctunch  on  the  door 
frame  when  hurrying  through  a  narrow  doorway  and  falling  on 
frozen  ground. 

Fractures  of  the  external  angle  of  the  ileum  or  point  of 
haunch  are  usually  followed  by  displacement  of  the  fractured 
portion.  The  same  is  true  of  fractures  of  the  neck  of  the  ileum. 
The  result  is  a  deformity  of  the  quarter. 

In  making  an  examination  of  these  parts  the  examiner  should 
see  that  the  horse  is  standing  squarely  on  its  feet,  and  then 
compare  the  conformation  of  the  two  quarters.  Fractures  of 
either  the  external  angle  or  the  neck  of  the  ileum  cause  the  quar- 
ter to  appear  narrow  and  low.  A  close  examination  may  enable 
the  examiner  to  differentiate  between  the  two  fractures.  Frac- 
tures of  the  neck  of  the  ileum  can  be  recognized  by  manipulating 
the  part  through  the  walls  of  the  rectum  or  vagina. 

The  degree  of  lameness  may  vary.  In  some  cases  there  may 
be  no  lameness  when  the  animal  walks,  but  a  slight  degree  of 
lameness  may  be  noticed  when  it  trots.  For  several  weeks  after 
the  injury  the  horse  may  be  unable  to  use  the  limb,  but  it  may 
eventually  make  nearly  a  complete  recovery. 

Atrophy  of  the  muscles  of  the  hip  or  quarter  (Fig.  44) 
should  not  be  mistaken  for  fractures  of  the  ileum.  This  con- 
dition involves  the  heavy  gluteal  muscles  and  may  occur  as  a 
complication  of  azoturia,  or  a  lameness  of  the  hind  limb  that 
is  usually  due  to  a  spavin. 
174 


DISEASES  OF  THE  HIND  LIMB 


175 


It  is  very  seldom  necessary  to  giye  fractures  of  tlie  ileiun 
any  special  care.  If  the  animal  is  yery  lame,  it  should  l)e  given 
a  narrow  stall,  and  placed  in  a  sling  until  it  can  support  its 
weight  on  the  limb.  The  same  treatment  is  indicated  in  cattle. 
It  is  not  adyisable  to  breed  a  mare  that  has  had  the  ileum  frac- 
tured. The  bony  enlargement  that  results  from  the  union  of  the 
broken  ends  of  the  bone  may  interfere  with  the  passage  of  the 
foetus  through  the  pelyic  cayity  and  cause  difficult  parturition. 

Luxation  of  the  Patella,  "  Stifle  Out." — This  is  a  common 
accident  in  horses  and  mules. 
Young,  immature  animals  are 
more  prone  to  displacement  of 
the  patella  than  when  mature. 
The  displacement  is  usually  up- 
ward or  outward.  Outward  dis- 
placement is  comparatiyely  rare. 

The  causes  of  "stifle  out  " 
may  be  described  as  follows: 
The  patella  or  knee-cap  rests  on 
a  pulley-like  articular  surface 
belonging  to  the  inferior  ex- 
tremity of  the  thigh-bone.  The 
external  lip  of  this  articular  surT 
face  is  smaller  than  the  internal 
lip.  The  patella  is  held  in  place  from  aboye  by  the  heayy 
muscles  of  the  anterior  region  of  the  thigh,  and  from  below,  by 
straight  ligaments  that  attach  it  to  the  leg-bone.  If  the  retaining 
structures  mentioned  become  relaxed,  the  patella  may,  when 
the  limb  is  extended,  become  so  displaced  as  to  rest  on  the 
superior  portion  of  the  external  lip.  Laxness  of  the  muscles  and 
ligaments  in  young  animals  is  a  predisposing  factor.  Hard 
work  that  tires  the  muscles  and  causes  them  to  become  relaxed, 
strains,  unusual  moyements,  as  kicking  in  the  stable  and  slip- 
ping, may  cause  this  accident.     Congenital  displacement  results 


Fig.   44. 


Atrophy   of   the  muscles  of  the 
quarter. 


176  NON-SPECIFIC  OR  GENERAL  DISEASES 

from  imperfect  development  of  the  external  lip  of  the  trochlea. 
Such  a  deformity  subjects  the  animal  to  frequent  luxations. 

The  symptoms  may  vary.  The  displacement  may  be  first 
noticed  when  the  horse  is  backed  out  of  the  stall  or  turned 
quickly.  A  slight  "  hitch  "  in  the  movement  of  the  limb  is  noted, 
that  is  followed  by  more  noticeable  flexion  of  the  hock  than 
normal.  In  case  the  luxation  is  more  permanent,  the  horse 
stands  quietly  with  the  affected  leg  held  stiffly  and  extended 
backward.  When  made  to  move  forward,  it  hops  on  the  well  leg 
and  carries  the  affected  one,  or  drags  it  on  the  toe.  If  both  limbs 
are  affected,  the  animal  is  unable  to  move.  The  inability  to 
move  the  limb  is  due  to  the  patella  resting  on  the  external  lip 
of  the  pulley  surface,  and  a  locking  of  the  stifle-  and  hock-joint. 

This  accident  is  annoying,  and  in  case  the  horse  is  subject 
to  it  should  be  considered  an  unsoundness. 

The  following  treaiment  may  be  recommended:  The  luxation 
may  be  reduced  in  the  large  majority  of  cases  by  backing  or 
turning  the  animal.  If  this  does  not  reduce  the  displacement, 
a  collar  should  be  placed  on  the  animal,  and  a  hobble  strap 
fastened  to  the  pastern  of  the  involved  limb.  One  end  of  a  long 
rope  is  tied  to  the  collar,  passed  backward  between  the  front 
limbs,  through  a  ring  in  the  hobble  and  back  over  the  outside  of 
the  shoulder  and  under  the  collar.  While  an  attendant  pulls 
the  limb  a  little  forward  with  the  rope,  the  operator  takes  hold 
of  the  foot  and  attempts  to  flex  the  limb,  at  the  same  time  pushing 
inward  on  the  patella.  After  reducing  the  luxation  it  is  advisable 
to  tie  the  rojDC  to  the  collar,  so  that  the  limb  is  carried  forward. 
This  prevents  the  animal  from  throwing  weight  on  the  foot. 
It  may  be  advisable  to  tie  the  animal  so  that  it  can  not  lie  down, 
if  the  foot  is  to  be  left  hobbled  for  a  few  days.  A  fly  blister 
should  be  applied  to  the  front  and  outside  of  the  stifle  and  the 
application  repeated  in  two  or  three  weeks. 

String-halt. — This  term  is  applied  to  a  peculiar  involuntary 
movement  of  one  or  both  hind  limbs  that  is  characterized  by  a 


DISEASES  OF  THE  HIND  LIMB  177 

sudden,  purposeless  flexion  of  the  hock-joint  (Fig.  45).  Horses 
that  are  slightly  affected  may  show  this  movement  of  the  hind 
limbs  when  first  exercised.  Other  horses  may  be  "  string-halted  " 
when  backed,  turned,  walked,  or  trotted,  and  fail  to  drive  out  of 
it.    The  cause  of  true  "  string-halt  "  is  not  known. 

The  treatment  recommended  is  surgical.     This  consists  in 


Fig.   45.— String-halt. 

cutting  the  tendon  of  the  peroneus  muscle.  The  seat  of  the 
operation  is  a  little  below  the  hock  and  on  the  external  face  of 
the  cannon. 

Spavin. — A  spavin  is  a  chronic  inflammation  of  the  articular 
faces  of  the  hock  bones,  ligaments  and  synovial  membranes.  The 
inflammation  may  result  in  the  formation  of  a  bony  enlargement 
on  the  inner  surface  of  the  region,  and  a  union  between  the  small 
bones  forming  the  lower  portion  of  the  hock^  and  the  upper 
extremities  of  cannon  and  lower  hbck  bones. 
12 


178 


NON-SPECIFIC  OR  GENERAL  DISEASES 


Fia.  46. — A  large  bone  apavia. 


The  predisposing  causes 
are  of  the  greatest  impor- 
tance. A  spavin  is  one 
of  the  unsoundnesses  of 
horses  that  maj  be  trans- 
mitted to  the  offspring. 
Young  colts  that  have 
heavy  bodies  and  are  fed 
a  fattening  ration  are  pre- 
disposed to  it.  Crooked 
hind  limbs,  small  hocks 
and  quarters  that  are 
heavily  muscled  are  pre- 
disposing factors.  The  ex- 
ternal causes  are  strains 
caused  by  slipping,  turn- 
ing quickly,  rearing,  pull- 
ing heavy  loads  and  kicks. 
Horses  three  or  four  years 
of  age  if  given  work  that 
favors  hock  strain,  such  as 
excavating  cellars,  may 
develop  a  spavin. 

The  symptoms  or  lame- 
ness are  more  character- 
istic than  in  most  diseases 
of  the  limb.  At  the  very 
beginning  of  the  inflam- 
mation, and  sometimes  for 
several  months  afterward, 
the  lameness  is  intermit- 
tent and  disappears  with 
exercise.  After  a  time  it 
is  pennanent.     It  is  char- 


DISEASES  OF  THE  HIND  LIMB 


179 


acterized  by  a  stilfiiess  of  the  hock.  The  extension  of  the 
hock  is  incomplete,  the  step  is  short  and  qnick,  the  animid 
"goes  on   its   toe"    and   the   wall   or   shoe    at   the   toe   shows 


Fig.  47. — Capped  hock. 


considerable  wear.  Because  of  the  stiffness  in  the  hock  the 
animal  raises  the  quarter  when  the  limb  is  carried  forward. 
Turning  toward  the  well  side  may  increase  the  lameness. 
The  spavin  test  may  be  of  value  in  diagnosing  lameness.     This 


180 


NON-SPECIFIC  OR  GENERAL  DISEASES 


consists  in  picking  up  tlie  foot  and  holding  the  hock  in  a  flexed 
position  for  a  few  minntes.  The  foot  is  then  dropped  to  the 
ground  and  the  animal  moved  off  at  a  brisk  trot.  If  the  lameness 
is  more  marked,  it  indicates  that  the  seat  is  in  the  region  of  the 
hock.  This  test  is  of  greatest  value  in  young  animals.  The 
bony  enlargement  can  usually  be  seen  best  if  the  examiner  stands 
in  front  and  to  one  side  of  the  animal.  The  hock  should  be 
observed  from  directly  behind  as  well.     The  hocks  of  both  limbs 

should  be  compared,  and  the  general 
conformations  of  the  other  joints  as 
well.  This  may  prevent  the  exam- 
iner from  mistaking  rough  hocks  for 
spavin  enlargements  or  "■  a  pair  "  of 
spavins  for  rough  hocks.  A  bony 
enlargement  does  not  always  accom- 
pany the  lameness,  and  a  spavin 
may  be  present  without  the  horse 
going  noticeably  lame. 

Tlie  prog7iosis  is  always  uncertain 
and  should  be  guided  somewhat  by 
the  conformation  of  the  limb,  char- 
acter of  the  work  required  of  the 
animal,  position  of  the  bony  enlarge- 
ment and  the  degree  of  lameness. 
The  size  of  the  enlargement  is 
changed  very  little  by  the  treatment. 
Veterinarians  report  recoveries  in  from  fifty  to  sixty  per  cent 
of  the  cases  treated. 

The  object  of  the  treatme^it  is  to  destroy  the  inflammation 
and  bring  about  a  union  between  the  bones.  The  treatment 
recommended  is  counterirritation  and  rest.  The  most  satisfac- 
tory method  of  counterirritation  is  firing  followed  by  blistering. 
Following  this  treatment,  the  horse  should  be  placed  in  a  stall 
and  given  no  exercise  for  a  period  of  five  or  six  weeks.     It  is 


Fig.  48. — Bog  spavins. 


DISEASES  OF  THE  HIND  LIMB 


181 


sometimes  advisable  to  repeat  the  counterirritatioii  if  the  results 
of  the  first  firing  are  unsatisfactory. 

Bog  Spavin. — Bog  spavin  is  an  extensive  distention  of  the 
capular  ligament  of  the  hock-joint  by  synovia  (Fig.  48).  It  is 
geuerallv  due  to  chronic  inflammation  of  the  synovial  membrane. 
This  blemish  or  unsoundness 
is  most  common  in  young 
horses.  Thorough  pin  (Fig. 
49)  involves  the  sheath  of  the 
large  tendon  only.  (Com- 
pare Figs.  48  and  49.) 

Certain  conformations  of 
the  hock  favor  the  develop- 
ment of  bog  spavin.  This  is 
especially  true  of  upright  and 
"  fleshy  "  hocks.  Hard  work 
may  cause  the  hocks  to  "  fill  " 
when  followed  by  a  brief 
period  of  rest.  The  common 
cause  is  a  sprain  due  to  slip- 
ping and  pulling  heavy  loads. 

The  following  symptoms 
may  be  noted :  Lameness  is 
not  a  common  symptom  of  bog 
spavin.  If  there  is  inflamma- 
tion present  or  the  articula- 
tion is  injured,  lameness  oc- 
curs. The  soft  swelling  that 
characterizes  the  bog  spavin 
is  most  prominent  toward  the  inside  and  front  of  the  region.  In 
the  upper  portion  or  hollow  of  the  hock,  and  on  the  inside  and  out- 
side, there  may  be  a  second  enlargement.  Smaller  enlargements 
may  be  present  in  other  regions.  All  of  the  swellings  feel  soft,  and 
pressure  on  any  one  of  them  moves  the  fluid  present  in  the  others. 


Fig.  49. — Thorough  pin.  Note  the  relation 
of  the  enlargement  to  the  tendon,  and  the  free- 
dom of  the  hocks  from  bog  spavin. 


182  NON-SPECIFIC  OR  GENERAL  DISEASES 

The  treatment  is  directed  at  the  removal  of  the  lameness. 
Acute  inflammation  resulting  from  spavin  may  be  relieved  by 
cold  applications  and  rest.  Chronic  lameness  should  be  given 
the  same  treatment  as  recommended  for  bone  spavin.  The 
enlargement  can  be  successfully  removed  in  growing  colts  by 
the  repeated  apiDlication  of  mild  blisters.  It  may  be  necessary 
to  continue  the  treatment  for  several  months.  The  removal 
of  the  enlargement  in  adult  horses  by  an  operation  is  recom- 
mended. The  greatest  caution  is  required  in  performing  this 
operation. 

Capped  Hock. — All  swellings  on  the  point  of  the  hock  are 
termed  "capped  hock"  (Fig.  47).  The  swellings  may  be  due  to 
an  injury  to  the  skin  and  the  subcutaneous  tissue,  or  more 
important  structures  may  be  involved,  as  the  subcutaneous  bursa, 
the  tendon,  or  the  synovial  bursa  or  sack. 

Capped  hock  is  caused  by  the  animal  kicking  in  the  stall 
or  in  harness,  shipping  in  freight  cars  and  lack  of  bedding  in  the 
stall.  Unless  the  deeper  structures  are  bruised  and  inflamed  the 
animal  shows  no  lameness. 

The  character  of  the  enlargement  varies.  When  the  injury 
is  superficial,  the  swelling  feels  firm,  or  pits  on  pressure.  Later 
it  may  become  more  firm  and  feel  like  a  loose,  thickened,  fibrous 
cap  for  the  hock.  Soft,  fluctuating  swellings  are  due  to  an 
inflammation  of  the  bursa.    Recent  injuries  feel  hot. 

The  preventive  treatment  consists  in  hobbling  the  hind  limbs 
of  a  horse  that  kicks  in  the  stable.  This  is  usually  necessary  only 
at  night.  It  may  be  advisable  to  pad  certain  parts  of  the  stall. 
Horses  that  are  transported  in  cars  should  be  protected  against 
injuries  during  transit  by  the  use  of  proper  care  and  such 
arrangement  of  the  animals  in  the  car  as  may  expose  them  to  the 
least  injury.  Recent  injuries  should  be  treated  by  the  applica- 
tion of  cold  and  rest. 

After  the  inflammation  has  subsided  tincture  of  iodine  or 
blisters  may  be  applied.     The  treatment  of  bursal  enlargements 


DISEASES  OF  THE  HIND  LIMB 


183 


is  surgical.  This  consists  in  opening'  the  bursa,  destroying  the 
lining  membrane  of  the  cavity  and  treating  the  part  daily  until 
healed.  The  operation  must  be  performed  carefully,  as  there 
is  danger  of  infection  with  irritating  organisms.  The  animal 
should  be  given  complete  rest  until  the  part  is  healed.  Tincture 
of  iodine  may  be  applied  to  the  enlargement  that  may  remain 
after  healing  has  occurred.  This  should  be  continued  daily  until 
the  skin  becomes  noticeably  irritated.  The  treatment  may  be 
repeated,  if  necessary,  after  an  interval  of  two  weeks. 


Fig.  50. — Curbs. 

Curb. — This  term  is  applied  to  all  swellings  on  the  posterior 
border  of  the  hock  (Fig.  50).  Thickenings  or  enlargements  in 
this  region  may  involve  a  variety  of  structures.  Thickening  of 
the  skin,  tendons  and  sheath  may  occur.  The  large  ligament 
that  extends  from  the  posterior  border  of  the  bone  that  forms 
the  summit  of  the  hock  to  the  external  splint  bone,  and  acts  as  a 
stay  for  the  point  of  the  hock,  is  the  structure  usually  involved 
in  curb. 


184  NON-SPECIFIC  OR  GENERAL  DISEASES 

Faulty  conformation  is  a  predisposing  cause.  A  narrow 
base  weakens  the  hock  at  this  point,  and  the  extreme  length  of  the 
bone  that  forms  its  summit  gives  the  powerful  muscles  attached  to 
it  greater  leverage  than  in  a  well-conformed  hock.  This  results 
in  strain  to  the  ligament  at  the  posterior  portion  of  the  region. 

The  exciting  causes  are  strains  resulting  from  jumping, 
slipping,  rearing,  heavy  pulling  and  bruising  of  the  part. 

In  examining  the  hock  for  curb  it  is  necessary  to  stand  to 
the  side  and  note  the  profile  of  the  posterior  border.  Excessive 
development  of  the  head  of  the  external  splint  bone  should  not 
be  mistaken  for  curb.  As  viewed  from  the  side,  the  posterior 
border  of  the  hock  should  appear  straight. 

The  curb  appears  as  a  swelling  on  this  straight  line.  It  varies 
in  size.  A  recent  curb  is  usually  hot  and  firm,  or  may  feel  soft  if 
enlargement  is  formed  by  fluid,  hard  if  formed  by  bone.  Lame- 
ness seldom  occurs,  but  if  present,  resembles  spavin  lameness. 

The  preventive  treatment  consists  in  selecting  for  breeding, 
animals  that  have  strong,  straight  hocks,  and  using  the  necessary 
care  in  handling  and  working  horses.  It  is  not  uncommon  for 
young  horses  at  the  time  they  are  broken  to  harness  to  develop 
a  curb.  This  may  be  prevented  to  a  large  degree  by  careful 
handling.  At  the  beginning  of  the  inflammation  the  application 
of  cold  and  hand  rubbing  is  indicated.  After  the  inflammation 
has  subsided  tincture  of  iodine  or  blisters  should  be  applied. 
Kest  is  a  necessary  part  of  the  treatment  early  in  the  inflamma- 
tion. If  the  lameness  does  not  respond  to  the  above  treatment, 
it  should  be  treated  the  same  as  for  bone  spavin. 

QUESTIONS 

1.  Describe  the  different  fractures  of  the  ileum  and  give  treatment. 

2.  Describe  string-bait  lameness  and  give  treatment. 

3.  Wbat  is  bone  spavin?     Describe  spavin  lameness. 

4.  Give  the  causes  and  treatment  of  bog  spavin. 

5.  Give  the  causes  and  treatment  of  capped  hock. 

6.  Give  the  causes  and  treatment  of  curb. 


PART  III 

THE  TEETH 


CHAPTER  XIX 

DETERMINING   THE   AGE   OF   ANIMALS 

General  Discussion. — The  teeth  are  the  passive  organs  of 
digestion.  They  are  hard  organs,  implanted  in  the  superior 
and  inferior  jaws  in  the  form  of  a  long  and  narrow  arch  that  is 
open  posteriorly.  The  free  portions  of  the  teeth  project  into 
the  mouth,  and  present  sharp  or  roughened  table  surfaces  for  the 


Fig.   51. — Head  of  young  horse  with  bone  cut  away,  and  showing  position  and  size  of  teeth. 

crushing  and  tearing  of  food.  In  solijieds  and  ruminants  the 
arch  is  interrupted  on  each  side  by  the  inter-dental  space  or  bars 
(Fig.  51).  The  teeth  that  form  the  middle  and  anterior  por- 
tion of  the  arch  are  termed  incisors  (Fig.  52).  Posterior  to  the 
incisors  are  the  canines  or  tusks,  and  fonning  the  arms  of  the 
arch  are  the  molar  teeth.    Animals  have  two  sets  of  teeth,  tem- 

187 


188  THE  TEETH 

porary  and  permanent.     The  following  table  gives  the  nnmber 
of  the  different  kinds  of  temporary  and  permanent  teeth. 

Temporary  Teeth  Permanent  Teeth 

Incisora  Canines  Molars  Incisors  Canines  Molars 

Solipeds     12          ..          12  12           4         24 

Ox 8          . .          12  8           0         24 

Sheep    8          ..          12  8           0         24 

Hog    12          . .          12  12           4         24 

The  tusks  or  canine  teeth  are  not  always  present  in  the 
female.  Kuminants  do  not  have  upper  incisor  teeth.  The  tem- 
porary teeth  are  erupted  either  before  or  within  a  few  days 
to  a  few  months  after  birth.  The  eruption  of  the  pennanent 
teeth  and  the  replacement  of  the  temporary  teeth  occur  at 
different  periods  up  to  the  age  of  four  and  one-half  years  (Fig. 
53).  It  is  well  to  keep  the  following  table  of  dentition  in  mind 
when  examining  the  mouths  of  animals  for  the  purpose  of 
determining  their  age."' 


Horses 

Cattle 

Hogs 

Teeth 

Temporary 

Permanent 

Temporary 

Perma- 
nent 

Temporary 

Perma- 
nent 

Incisors : 
Centrals 

First  laterals..  . 
Second  laterals. 

At  birth 
4-6  wks. 

yrs.    mux. 

2  0 

3  6 

At  birth 

At  birth 

5-12  days 

12-18  days 

At  birth 
At  birth 
At  birth 

yTS.   mos 

1  8 

2  9 

3  6 

4  6 

2       6 
1       G 
3 

1  6 
2 

2  6 

At  birth, 
or  3-4 
weeks 

8-12  wks. 

At  birth 

7  weeks 
8-28  days 
8-28  days 

mos. 
12 

18 

Corners 

Molars: 
First 

0-9  mos. 

At  birth 
At  birth 
At  birth 

4      G 

2      6 

2  G 

3  G 
10-12 

2 

4-5 

9 

5 

Second 

Third 

14 
13 

rOurth 

13 

l'"iith    

5 

Sixth       

9 

Seventh 

18 

Canines  or  tusks 

4-5 

9 

*  This  table  is  from  dentition  tables  given  in  "  Age  of  the  Domestic 
Animals,  "  by  Iluidekoper. 


DETERMINING  THE  AGE  OF  ANIMALS 


189 


In  determining  the  age  of  the  diflfercnt  domestic  animals 
by  the  development  and  appearance  of  the  teeth,  most  of  the 
attention  is  given  to  the  lower  incisor  teeth.  Up  to  the  fifth 
year,  the  age  of  the  horse  or  ox  can 
be  easily  determined  by  the  emption 
and  replacement  of  the  incisors. 

At  one  year  of  age  the  colt  has 
a  fully  developed  set  of  temporary 
incisors.  The  ruminant's  incisors 
at  this  age  all  show  wear. 

The  two-year-old  colt  shows  a  well- 
worn  set  of  incisor  teeth,  and  the 
ruminant  at  this  age  has  replaced  the 
nippers  or  centrals. 

The  third,  fourth  and  fifth  years 
are  indicated  by  the  replacement  of 
the  temporally  nippers,  dividers  and 
comers  in  the  horse,  and  the  first 
and  second  dividers  and  corner  teeth 
in  ruminants. 

In  the  horse  the  permanent  nip- 
pers are  full  growm  and  in  wear  at 
three  years  of  age;  the  permanent 
dividers  are  full  grown  and  in  wear 
at  four  years  of  age;  and  the  per- 
manent corners  are  full  grown  and  in 
wear  at  five  years  of  age.  The  table 
surfaces  of  tlie  incisor  teeth  of  a  five- 
year-old  horse  show  different  degrees 
of  wear.  At  this  period  in  the  ani- 
mal's age,  the  nippers  have  been  in  wear  two  years,  the  dividers 
one  year,  and  the  corners  are  beginning  to  show  wear.  In  rumi- 
nants, all  of  the  chisel-shaped  table  surfaces  of  the  incisors  show 
considerable  wear  when  the  animal  is  five  years  old. 


Fig.  52. — Longitudinal  .section 
of  incisor  tooth:  (A)  cup;  (B) 
cement;  (C)  enamel;  (D)  ivory; 
and  (E)  pulp  cavity.  (After 
Huidekoper.) 


190 


THE  TEETH 


After  the  animal  has  a  full  set  of  permanent  teeth,  we  judge 
the  age  hy  the  degree  of  wear  or  the  appearance  of  the  table 
surfaces  of  the  incisors,  their  shape,  the  angle  with  which  they 
meet  and  the  general  appearance  of  the  head. 

There  are  several  ditlerent  factors  that  may  cause  the  wear 
on  the  teeth,  and  the  appearance  of  their  tahle  surfaces  to  vary 
in  the  different  individuals.     The  two  factors  that  are  of  the 


Fig.   53. — Cross-section  of  head  of  young  horse  showing  replacement  of  molar  tooth  (A). 

most  importance  are  the  quality  of  the  teeth  and  the  character 
of  feed.  Soft  teeth  wear  more  quickly  than  hard  teeth,  and  the 
teeth  of  horses  that  feed  over  closely  cropped  and  sandy  pastures 
wear  rapidly  because  of  the  dirt  and  grit  present  on  the  short 
grass.  Tliis  variation  in  the  wear  is  of  little  importance  to  the 
person  who  must  judge  the  age  of  a  horse  that  he  expects  to 
purchase  by  the  condition  of  the  teeth.  In  reality,  a  horse  is 
just  as  old  as  the  wear  on  the  teeth  and  his  general  appearance 


DETERMINING  THE  AGE  OF  ANIMALS 


191 


indicate.  In  order  to  stand  severe  work  the  animal  must  be 
able  to  masticate  the  feed,  and  prepare  it  for  digestion  in  the 
stomach  and  intestines.  The  degree  of  wear  on  the  molar 
teeth  may  be  indicated  by  the  wear  on  the  incisors.  The  general 
condition  of  the  horse  and  his  ability  to  stand  hard  work  depend 
very  largely  on  the  condition  of  the  table  surfaces  of  the  molars. 

It  is  very  difficult  to  judge  the  age  of  horses  that  have  de- 
formed mouths  or  that  are  in  the  habit  of  crib-biting,  because 
of  the  irregularity  in  the  wear  of  the  incisors. 

When  examining  the  teeth  for  the  purpose  of  determining 


Fig.  54. — Transverse    section    of   incisor   tooth:      (A)    peripheral    cement;    (B)    peripheral 
enamel;  (C)  ivory;  (D)  central  enamel;  and  (E)  central  cement.     (After  Huidekoper.) 

the  horse's  age,  the  shape  of  the  incisors,  the  angle  with  which 
they  meet  and  the  appearance  of  their  table  surfaces  should  be 
observed.  The  teeth  of  young  horses  show  more  or  less  yellowish 
cement.  At  about  seven  years  of  age  the  anterior  faces  of  the 
teeth  are  usually  white,  later  a  yellowish  color.  The  teeth  of 
middle-aged  horses  may  be  long,  and  in  aged  animals,  narrow 
and  short.  The  incisors  meet  at  a  more  acute  angle  in  old  than 
young  horses. 

The  free  portion  of  the  incisor  tooth  is  flattened  from  l^eipre 
to  behind.  At  the  level  of  the  gums  its  two  diameters  are  about 
the  same,  but  the  portion  of  the  tooth  imbedded  in  the  jaw  bone 


192 


THE  TEETH 


is  flattened  from  side  to  side.  As  the  tooth  Ijecomes  worn  off, 
the  length  of  the  free  portion  is  maintained  by  a  pushing  out  of 
the  tooth,  and  a  corresponding  shortening  of  the  portion  that  is 
fixed  or  imbedded  in  the  jaw. 

The  table  surface  of  the  unworn  incisor  tooth  is  covered  with 

enamel,  and  in  the  middle  por- 
tion the  enamel  forms  a  deep  cup. 
After  tlie  tooth  has  become  worn 
the  margin  of  the  table  portion  is 
then  limited  by  a  ring  of  enamel. 
This  is  termed  the  encircling 
enamel  ring.  The  central  portion 
of  the  taljle  shows  a  second  ring, 
the  central  enamel  ring,  that 
limits  the  cup  margin  (Fig.  54). 
As  the  table  surface  repre- 
sents a  cross  section  of  the  tooth, 
its  appearance  and  shape  will 
then  depend  on  the  portion  of  the 
tooth  that  it  represents.  From 
year  to  year,  there  is  a  gradual 
shortening  in  the  lateral  diameter, 
and  an  apparent  increase  in  the 
diameter  from  before  to  behind. 
These  changes  in  shape  are  from 
a  long,  narrow  table  surface  to  an 

Fig.  55.— Table  surfaces  of  nippers  at  OVal,  frOUl  OVal  tO  circukr  and 
difforentages.  ^  four  years;  B.  six  years;  f^.^^^j^  circular  tO  triaUgular  (Fig. 
C ,  nine  years,  and /),  fifteen  years  of  age.  '-  \        e^ 

55).  As  the  original  free  por- 
tion of  the  tooth  wears  off,  the  cup  becomes  shallow  and  smaller 
until  the  remnant  is  represented  by  a  mere  dot  of  enamel  that 
finally  disappears  from  the  posterior  portion  of  the  table.  After 
the  cup  has  moved  from  the  central  portion  of  the  crown 
and  occupies  a  more  posterior  position,  the  dental  star,  which 


DETERMINING  THE  AGE  OF  ANIMALS  193 

represents  a  cross  section  of  the  pnlp  cavity,  pnts  in  its  appear- 
ance. It  first  takes  the  form  of  a  Ijrown  or  dark  streak,  and 
hiter  a  circuhir  dark  spot  which  gradually  increases  in  size  with 
the  wear  on  the  tooth  and  the  age  of  the  animal. 

The  following  changes  in  the  shape  and  appearance  of  the 
incisor  teeth  of  the  average  horse  occur  in  the  different  years. 
Unless  otherwise  mentioned,  the  statements  made  regarding  the 
appearance  and  wear  on  the  table  surfaces  apply  to  the  lower 
incisor  teeth. 

Six  Years. — The  table  surfaces  form  the  most  accurate  guide. 
The  cups  of  the  nippers  tend  to  an  oval  form.  The  corner  teeth 
have  been  in  wear  one  year  at  this  time.  The  cup  is  deep  and 
the  posterior  margin  may  show  little  wear.  It  is  not  uncommon 
to  meet  with  corners  that  possess  irregularly  developed  tables, 
and  have  cups  with  posterior  margins  that  are  thin  and  do  not 
come  into  wear  until  later.  For  this  reason,  it  is  not  best  to 
depend  on  the  appearance  of  the  corner  teeth  alone. 

Seven  Years. — The  teeth  are  usually  whiter  than  the  previ- 
ous year.  The  profile  of  the  upper  corner  teeth  shows  a  notch 
in  the  posterior  portion  of  the  table  surface.  This  is  due  to  the 
superior  corners  overhanging  the  inferior  corner  teeth  pos- 
teriorly, resulting  in  this  portion  not  wearing  away.  This  notch 
is  sometimes  slightly  in  evidence  the  previous  year.  The  cups 
in  the  corners  are  smaller  and  the  worn  surface  larger  than  at 
six.  The  nippers  show  oval  table  surfaces  and  the  dividers  are 
beginning  to  take  on  this  shape.  The  shifting  of  the  cups  toward 
the  posterior  portion  of  the  tables  of  the  nippers  and  dividers 
is  noticeable. 

Eight  Years. — As  viewed  from  the  side,  the  profile  of  the 
teeth  shows  a  very  noticeable  increase  in  the  ol)li(|uity  with  which 
they  meet.  The  posterior  borders  of  the  corners  show  consider- 
able wear.  The  notch  in  the  superior  corners  is  still  present, 
but  as  the  teeth  come  more  nearly  in  apposition  it  may  begin  to 
disappear.  All  of  the  inferior  tables  are  level.  The  nippers  and 
13 


194  THE  TEETH 

dividers  are  oval  in  shape,  and  the  cups  have  become  decidedly 
narrow.  The  nippers  show  a  well-defined  dark  streak  just  in 
front  of  the  cups.    This  is  the  beginning  of  the  dental  star. 

Nine  Years. — The  appearance  of  the  table  surface  is  more 
characteristic  at  this  time  than  the  previous  year.  The  cups  are 
less  prominent  and  the  plainness  or  smoothness  of  the  inferior 
table  is  more  noticeable.  The  nippers  are  round,  the  cups  tri- 
angular and  the  dark  streak  narrower  and  more  distinct  than  the 
previous  year.  The  dividers  are  becoming  round  and  the  corner 
teeth  are  oval. 

Ten  Years. — The  teeth  are  more  oblique  than  in  the  eight- 
year-old  and  nine-year-old  mouth.  The  table  surfaces  of  the 
inferior  nippers  are  decidedly  rounded,  the  cups  are  small, 
triangular  and  situated  well  toward  the  posterior  borders.  The 
dark  brown  streak  or  dental  star  is  situated  in  the  central  portion 
of  the  nippers  and  dividers.  The  tables  of  the  dividers  are 
round. 

Eleven  Years. — The  tables  of  the  corner  teeth  are  rounded. 
The  dark  streak  or  dental  star  is  present  in  all  of  the  teeth,  and 
the  remnants  of  the  cups  appear  as  small  rings  or  spots  of  enamel 
near  to  the  posterior  borders  of  the  tables.  The  notch  in  the 
superior  corners  may  reappear  at  this  time. 

Twelve  Years. — The  profile  of  the  teeth  when  viewed  from 
the  side  is  quite  oblique.  The  table  surfaces  of  all  the  incisors 
ai'e  round.  But  a  trace  of  the  cup  renuiins  in  the  inferior 
incisors.  The  head  of  the  animal  is  beginning  to  show  age. 
The  inferior  border  of  the  jaw  bone  appears  narrower,  or  sharper 
than  in  the  young  horse. 

Thirteen  Years. — All  of  the  specks  of  enamel  or  the  rem- 
nants of  the  cups  are  gone  from  the  lowel"  incisors.  A  larger 
notch  may  be  j)rcscnt  in  the  upper  corner  teeth  than  at  twelve. 
The  tables  of  the  inferior  ni])pers  are  becoming  triangular  and 
show  a  small,  dark  spot  or  dental  star. 

Fourteen  Years. — The  tables  of  the  inferior  nippers  are 


DETERMINING  THE  AGE  OF  ANIMALS  195 

triangular,  and  the  dental  star  appears  as  a  dark  round  spot  in 
both  the  nippers  and  dividers. 

Fifteen  Years. — The  angle  with  which  the  teeth  meet  is 
greater  than  at  twelve,  the  teeth  are  smaller  and  dental  stars 
are  represented  by  dark  round  spots  in  all  of  the  inferior  incisors. 
The  tables  of  the  nippers  and  dividers  are  triangular. 

Seventeen  Years. — All  of  the  tables  of  the  lower  incisor 
teeth  are  triangular.  The  teeth  are  narrower  and  smaller  than 
at  fifteen.  The  profile  of  the  incisors,  viewed  from  the  side,  is 
quite  aniiiilar.     The  dental  stars  are  prominent. 

Nineteen  Years. — All  of  the  signs  of  the  seventeen-year-old 
mouth  are  more  prominent.  The  cups  have  usually  disappeared 
from  the  upper  incisors. 

QUESTIONS 

1.  Name  the  different  kinds  of  teeth;   state  the  arrangement  and  number. 

2.  How  is  the  age  of  an  animal  determined? 

3.  Give  the  time  of  replacement  of  the  temporary  incisor  teeth. 

4.  How  is  the  age  of  the  animal  determined  between  the  fifth  and  ninth 

years? 

5.  \Miat   changes   in  the  appearance   of  the   table   surfaces  occur  between 

ten  and  fifteen  years  of  age? 


CHAPTER  XX 
IRREGULARITIES  OF  THE  TEETH 

Parrot-mouth,  Lantern-jaw  and  Scissor-mouth. — The  com- 
mon deformities  of  the  jaw  and  teeth  are  the  overshot  or  parrot- 
mouth,  the  undershot  or  lantern-jaw,  and  the  scissor-mouth. 
These  different  deformities  result  in  unequal  wear  on  the  table 
surfaces  of  the  incisors  and  molars.  In  both  the  overshot  and 
undershot  jaws,  the  incisor  teeth  become  abnormally  long.  In 
the  parrot-mouth,  the  wear  occurs  on  the  posterior  face  of  the 
superior  and  the  anterior  face  of  the  inferior  incisors,  the  teeth 
becoming  worn  to  rather  a  sharp  edge,  depending  on  the  degree 
of  the  deformity.  In  the  lantern-jaw,  the  wear  occurs  on  the 
posterior  face  of  the  lower  and  the  anterior  face  of  the  superior 
row  of  incisors,  the  teeth  taking  on  somewhat  the  same  shape  as 
the  parrot-mouth.  The  greater  the  deformity  and  the  older  the 
horse  becomes,  the  more  difficult  it  is  for  the  animal  to  feed  or 
graze  on  pasture. 

In  all  horses,  the  two  rows  of  molar  teeth  are  wider  apart  in 
the  superior  than  in  the  inferior  jaw.  This  results  in  the  ex- 
ternal border  of  the  tables  of  the  superior  row  of  molars  becoming 
longer,  or  projecting  further  downward  than  the  internal  border. 
The  wear  on  the  table  surfaces  of  the  inferior  row  of  molars 
is  just  the  opposite  of  the  superior  row.  In  the  scissor-mouth  the 
wear  takes  place  largely  on  the  internal  face  of  the  superior  and 
the  external  face  of  the  inferior  row  of  molars.  The  teeth  be- 
come worn  to  more  or  less  of  a  blunt  cutting  edge,  and  after  a 
time  the  molars  come  together  somewhat  like  the  jaws  of  a 
pair  of  scissors.  A  horse  with  a  badly  deformed  scissor-mouth 
is  unable  to  grind  the  feed,  and  unless  given  special  care,  suffers 
severely  from  innutrition. 
196 


IRREGULARITIES  OF  THE  TEETH  197 

The  treatment  of  deformed  mouths  consists  in  removing  the 
irregular  or  unworn  portion  of  the  teeth  by  means  of  the  tooth 
float  and  cutters.  This  attention  should  be  given  earlv  before  the 
free  portion  of  the  tooth  has  become  excessively  long  and  irregu- 
lar. This  should  be  followed  by  dressing  the  teeth  every  six  or 
twelve  months. 

Sharp  Lateral  Borders  on  the  Molar  Teeth. — This  is  a  very 
common  condition  in  horses.  The  external  border  of  the  superior 
and  the  internal  border  of  the  inferior  row  of  molars  wear  away 
slowly,  and  sometimes  become  quite  sharp.  This  is  objection- 
able because  the  sharp  points  lacerate  the  mucous  membrane  of 
the  cheek  and  tongue,  and  the  mastication  of  the  feed  is  seriously 
interfered  with. 

This  condition  is  caused  by  an  excessive  difference  in  the 
width  of  the  jaws,  unusually  prominent  ridges  of  enamel  on  the 
external  face  of  the  superior  molars,  and  any  conditions  that 
may  limit  the  movements  of  the  jaw. 

The  following  symptoms  may  be  noted.  The  animal  has 
difficulty  in  masticating  the  feed  because  of  injury  to  the  cheeks 
or  tongTie  by  the  sharp  points  of  enamel.  This  condition  may 
be  indicated  by  holding  the  head  to  one  side.  Salivation  is 
usually  present.     Acute  indigestion  and  innutrition  may  occur. 

By  examining  the  teeth,  their  condition  can  be  determined. 
The  sharp  borders  may  be  removed  by  dressing  or  floating  the 
teeth.  It  is  advisable  in  the  majority  of  horses  to  float  the  teeth 
at  least  once  in  every  twelve  months. 

Irregularities  in  the  Table  Surface  of  the  Molar  Teeth. — 
Horses  eight  years  of  age  or  older  frequently  have  irregular 
molars  (Fig.  56).  This  is  due  very  largely  to  the  difference  in  the 
quality  of  the  teeth.  The  harder  molars  do  not  wear  off  as  rapidly 
as  the  softer  ones.  This  results  in  the  table  surfaces  of  the  rows  of 
molars  becoming  wavy  or  step-like  in  outline.  Sometimes  the 
first  or  sixth  molar  overhangs  or  projects  beyond  the  corre- 
sponding tooth  of  the  opposite  jaw.    When  this  occurs,  the  over- 


198 


THE  TEETH 


hanging  portion  may  become  long  and  sharp.     A  molar  tooth 
becomes  excessively  long  if  the  opposite  one  is  decayed  or  removed. 
The  symptoms  are  very  much  the  same  as  when  the  borders 
of  the  molars  are  sharp. 


FlQ.   56. — Teeth  showing  uneven  wear  occurring  in  old  horses. 

The  treatment  consists  in  levelling  the  tables  as  frequently 
as  necessary  by  cutting  off  the  longer  projections,  and  removing 
the  sharp  edges  with  a  tooth  float. 

Smooth  Mouth.— Tn  old  age  tlie  tables  of  the  molar  teeth 
may  become  so  smooth  that  the  horse  cannot  grind  or  masticate 


IRREGULARITIES  OF  THE  TEETH 


199 


the  feed.  "When  all  of  the  molars  are  in  this  condition,  a  nibbing 
sound  may  be  noted  when  the  animal  is  masticating  hay.  After 
attempting  to  chew  the  hay,  it  may  be  dropped  from  the  mouth. 
Innutrition  always  occurs. 

The  treatment  consists  in  feeding  chops  and  soft  feeds. 

Dental  Diseases. — Inflammation  of  the  alveolar  periosteum 
is  a  common  dental  disease  in  domestic  animals.  This  is  an 
inflammation  of  the  alveolar  dental  membrane  that  fixes  the 
tooth  in  the  tooth  cavity. 


Fig.  57. — Fistula  of  jaw.    This  condition  was  the  result  of  neglected  treatment 
of  decayed  teeth. 

Injuries  to  the  gums  and  cracks  or  fissures  in  the  tooth  are 
the  common  causes.  Caries  or  tooth  decay  is  not  uncommon. 
The  predisposing  factor  is  a  poor  quality  of  enamel  and  dentine. 
The  process  of  decay  is  assisted  by  micro  organisms. 

The  early  symptoms  may  escape  notice.  Slobbering,  masti- 
cating on  one  side,  holding  the  head  to  one  side,  retained  masses 
of  food  in  the  mouth  and  a  disagreeable  odor  frequently  occur. 
Caries  may  be  indicated  at  first  by  a  dark  spot  on  the  table  of 
the  tooth,  later  by  a  cavity.     In  horses,  inflammation  of  the 


200  THE  TEETH 

alveolar  membrane  results  in  a  bony  enlargement  on  the  side  of 
the  face  if  the  superior  molar  is  involved.  A  swelling  of  the 
jaw  and  fistula  may  result  if  a  lower  molar  is  involved  (Fig.  5Y). 
The  treatment  consists  in  the  prompt  removal  of  the  tooth. 
This  is  more  difficult  in  young  animals  than  it  is  in  the  middle- 
aged  or  old.  Unless  the  tooth  is  already  loosened  it  may  be 
necessary  to  remove  it  by  trephining. 

QUESTIONS 

1.  Describe  the  appearance  of  the  teeth  in  an  overshot  or  undershot  jaw. 

2.  Describe  the  appearance  of  sharp  molar  teeth;  a  scissor-mouth. 

3.  What  are  the  causes  of  decayed  teeth? 


PART  IV 

SURGICAL  DISEASES 


CHAPTER  XXI 
INFLAMMATION  AND  WOUNDS 

Inflammation  is  a  pathological  condition  of  a  tissue,  char- 
acterized by  altered  function,  disturbance  of  circulation,  and 
destructive  and  constructive  changes  in  the  irritated  part.  Heat, 
redness,  swelling,  pain  and  disturbed  function  are  the  symptoms 
which  characterize  inflammation. 

The  changes  in  the  circulation  occurring  in  inflammation  are 
as  follows :  (1)  An  increase  in  the  rate  of  the  blood-flow  through 
the  blood-vessels  of  the  part  and  their  dilation;  (2)  diminished 
velocity  followed  by  the  blood-flow  becoming  entirely  suspended ; 
(3)  following  the  retardation  or  suspension  of  the  blood  stream, 
white  blood-corpuscles  accumulate  along  the  w'alls  of  the  small 
veins  and  capillaries ;  (4)  white  and  red  blood-corpuscles  migrate 
from  the  vessels  into  the  neighboring  tissue,  and  blood-serum 
transudes  through  the  walls  of  the  vessels,  forming  tlie  inflamma- 
tory swellings.  The  red  blood-cells  do  not  escape  from  the  blood- 
vessels in  any  numbers  unless  the  walls  of  the  blood-vessels 
become  injured  or  badly  diseased. 

The  causes  of  inflammation  may  be  grouped  under  the  fol- 
lowing heads :  mechanical,  chemical,  thermic  and  infectious. 
The  mechanical  or  traumatic  causes  commonly  produce  in- 
flammation in  domestic  animals.  These  are  kicks,  strains  of 
tendons,  ligaments  or  muscles  and  wounds.  Inflammation 
originating  from  injuries  very  frequently  changes  to  an  in- 
fectious form,  through  the  infection  of  the  part  by  bacteria. 
Bruised  tissue  may  become  infected  with  pus-producing  organ- 
isms, and  an  abscess  or  local  swelling  form.  All  accidental 
wounds  in  domestic  animals  become  more  or  less  infected  by 
irritating  microorganisms. 

The  following  symptoms  occur  in  local  inflammation.     In- 

203 


204  SURGICAL  DISEASES 

creased  heat  in  the  part  is  an  important  symptom.  It  is  due  to 
the  increased  blood-tlow  to  the  part.  Because  of  the  pigmented, 
hairy  skin  of  domestic  animals,  redness  is  of  little  value  in 
locating  superficial  inflammation.  Swelling  is  a  valuable  local 
symptom.  It  is  produced  by  the  inflammatory  exudates.  Pain 
results  from  the  pressure  on  the  sensory  nerves  by  the  in- 
flammatory swelling.  For  example,  the  laminix?  of  the  foot  are 
imprisoned  between  the  horny  wall  and  the  pedal  bone.  This 
structure  is  well  supplied  with  sensory  nerves,  and  when  it 
becomes  inflamed  and  swollen,  the  tissues  are  subject  to  severe 
pressure  and  the  pain  is  severe.  Inflammation  of  a  tendon  re- 
sults in  lameness  ;  of  the  udder,  in  suspension  of  milk  secretions ; 
and  of  the  stomach  by  interference  with  digestion  of  the  feed. 
Such  symptoms  may  Ije  grouped  under  the  head  of  disturbed 
functions. 

The  character  of  an  inflammation  is  largely  modified  by  the 
nature  of  the  tissue  in  which  it  occurs.  A  serous  inflammation 
is  characterized  by  serous,  watery  exudates.  This  form  occurs 
in  the  serous  membranes,  nmcous  membranes  and  skin.  Blisters 
on  the  skin  and  inflammation  of  bursas  (capjied  hock  and  shoe 
boil)  are  examples  of  this  type.  Sero-fibrinous  inflammations, 
such  as  occur  in  pleurisy  and  peritonitis,  are  common.  Chronic 
inflammation  commonly  results  in  new  formations  of  tissue, 
and  it  is  named  according  to  tlie  character  of  the  new  tissue 
formed,  as  ossifying,  adhesive,  and  fibrous  inflammation.  Pus- 
forming  bacteria  produce  suppurative  inflammation.  Such  dis- 
eases as  tuberculosis,  glanders  and  hog-cholera  are  specific  in- 
flammations. Specific  infectious  diseases  may  be  classed  as 
generalized  inflammation,  as  they  usually  involve  the  entire 
body. 

Inflannnation  terminates  in  resolution  when  the  serum  is 
reabsorbed  by  the  blood-vessels  and  lymphatics,  the  living  blood- 
cells  find  their  way  back  into  the  circulation  and  the  dead  cells 
disintegrate  and  are  taken  up  by  the  vessels.     The  time  required 


INFLAMMATION  AND  WOUNDS  205 

for  the  tissues  to  return  to  the  normal  varies  from  a  few  hours 
to  several  weeks.  An  acute  inflammation  may  end  in  the  chronic 
form.  This  may  then  terminate  in  new  formations,  such  as 
adhesions,  fibrous  thickenings  and  bony  enlargements.  Severe 
inflammation,  especially  if  localized  and  superficial,  may  re- 
sult in  death  of  the  part  or  gangrene. 

The  following  treatment  is  recommended:  The  cause  of 
the  irritation  to  the  tissue  must  be  removed.  It  is  very  essential 
that  the  part  be  rested.  The  necessary  rest  may  be  obtained 
in  different  ways.  Inflamed  tendons,  ligaments,  and  muscles 
may  be  rested  by  placing  the  animal  in  a  sling,  standing  it  in  a 
stall,  or  fixing  the  part  with  bandages.  Eest  of  the  stomach  or 
intestinal  tract  may  be  obtained  by  feeding  a  light  diet,  or 
withholding  all  feed.  Comfortable  quarters,  special  care  and 
dieting  the  animal  are  important  factors  in  the  treatment  of 
inflammation. 

The  agents  used  in  the  treatment  of  superficial  and  localized 
inflammation  are  heat,  cold,  massage  and  counter-irritation. 
Heat  is  indicated  in  all  inflammations,  excepting  when  of 
bacterial  origin.  It  stimulates  the  circulation  and  reabsorption 
of  the  inflammatory  exudates,  und  by  relaxing  the  tissues  helps 
greatly  in  relieving  pain.  Cold  is  more  eft'ective  in  the  highly 
acute  and  septic  (suppurative)  inflammation.  Its  action  con- 
sists principally  in  the  contraction  of  the  dilated  blood-vessels. 
Continuous  irrigation  of  the  part  with  cold  water  is  the  most 
satisfactory  method  of  applying  cold.  Massage  is  a  very  im- 
portant method  of  treating  superficial  inflammation.  Mild, 
stimulating  liniments  are  usually  used  in  connection  with  hand- 
rubbing  or  friction.  Chronic  inflammation  is  usually  treated 
with  counter-irritants.  Blistering  and  firing  are  the  most 
important  methods  of  treatment.  Such  counter-irritation  makes 
possible  the  absorption  of  the  inflammatory  exudates  by  chang- 
ing the  chronic  inflammation  to  the  acute  form. 

Wounds. — A  wound,  in  the  restricted  sense  that  the  term  is 


206  SURGICAL  DISEASES 

commonly  used,  includes  only  such  injuries  that  are  accompanied 
hj  breaks  or  divisions  of  the  skin  and  mucous  membrane.  It  is 
usually  an  open,  hemorrhagic  injury. 

If  the  tissues  are  severed  by  a  sharp  instrument  and  the 
edges  of  the  wound  are  smooth,  it  is  classed  as  an  incised  or 
clean-cut  wound.  This  class  is  not  commonly  met  with  in  do- 
mestic animals  outside  of  operative  wounds. 

When  the  tissues  are  torn  irregularly,  the  injury  is  classed 
as  a  lacerated  wound.  A  barb-wire  cut  is  the  best  exam23le  of 
this  class. 

A  contused  wound,  is  an  injury  caused  by  a  blunt  object. 
Such  injuries  may  be  divided  into  superficial  and  deep.  Super- 
ficial-contused wounds  may  be  an  abrasion  to  the  skin  or  mucous 
surface.  Deep-contused  wounds  may  be  followed  by  loss  of 
tissue  or  sloughing,  and  may  present  irregular,  swollen  margins. 
Such  injuries  are  commonly  caused  by  kicks. 

Punctured  wcuvds  are  many  times  deeper  than  the  width 
of  the  opening  or  break  in  the  skin  or  mucous  membrane.  This 
class  is  produced  by  sharp  objects,  such  as  nails,  splinters  of 
wood,  and  forks. 

Sometimes,  wounds  are  given  special  names,  as  gun-shot, 
poisoned,  and  open  joint,  depending  on  the  nature  of  the  cause 
and  region  involved. 

Bleeding  or  hemorrhage  is  the  most  constant  s_\Tnptom. 
The  degree  of  hemorrhage  depends  on  the  kind,  number  and 
size  of  the  blood-vessels  severed.  In  arterial  hemorrhage,  the 
blood  is  bright  red  and  spurts  from  the  mouth  of  the  cut  vessel. 
In  venous  hemorrhage,  the  blood  is  darker  and  flows  in  a  con- 
tinuous stream.  In  abrasions  and  superficial  wounds  capillary 
hemorrhage  occurs.  Death  may  follow  severe  hemorrhage. 
Weak  pulse,  general  weakness,  vertigo,  loss  of  consciousness  and 
death  may  result  if  one-third  of  the  total  quantity  of  blood  is 
lost.  Unthriftiness  and  general  debility  may  follow  the  loss  of 
a  less  quantity  of  blood. 


INFLAMMATION  AND  WOUNDS 


207 


The  following  sympioms 
may  be  noted  in  the  differ- 
ent kinds  of  wounds:  The 
sensitiveness  to  the  pain  re- 
sulting from  accidental  or 
operative  wounds  varies  in 
the  different  individuals  and 
species,  and  in  the  kind  of 
tissue  injured.  Injuries  to 
the  foot,  periosteum,  skin 
and  mucous  membrane  are 
more  painful  than  are  in- 
juries to  cartilages  and  ten- 
dons. The  appearance  of 
the  wound  varies  in  the  dif- 
ferent regions  and  the  differ- 
ent tissues. 

If  the  tissues  are  badly 
torn  or  bruised,  swelling 
and  sloughing  may  occur. 
If  the  wound  is  transverse 
to  the  muscular  fibres,  it 
gaps  more  than  when  paral- 
lel to  the  muscle.  Wlien  in- 
fected by  irritating  organ- 
isms, open  and  punctured 
wounds  (Fig.  58)  become 
badly  swollen,  discharge  pus 
freely  and  heal  slowly  with 
excessive  granulations. 
Wounds  involving  tendons, 
bursie  and  closed  articula- 
tions become  swollen  and 
discharge  synovia.    Wounds 


FiQ.  58. — A  large  hock  caused  by  a  punctured 
wound  of  the  joint. 


208 


SURGICAL  DISEASES 


involving  muscles,  tendons  and  bursiv  nsnally  cause  lameness, 
and  when  involving  a  special  organ,  interfere  with,  or  destroy, 
its  function.  Extensive  or  serious  wounds  may  be  followed  by 
loss  of  appetite.  An  abnormal  body  temperature  and  other 
symptoms  characteristic  of  the  different  forms  of  blood  poison- 
ing may  follow  infection  of  the  injured  tissues  by  certain  germs. 
The  rapidity  with  which  wounds  heal  depends  upon  the  kind 

of  tissue  injured  and  the 
amount  to  be  replaced,  the 
degree  of  motion  in  the  part, 
the  kind  and  degree  of  infec- 
tion and  irritation  and  the 
general  condition  of  the  ani- 
mal. In  general,  skin  and 
muscles  heal  rapidly,  tendons 
slowly,  cartilages  unsatisfac- 
torily and  nerve  tissue  very 


slowlv 


Healing    is 


greatly 


interfered  with  by  movement 
of  the  part  (Fig.  59).  The 
more  nearly  the  part  can  be 
fixed  or  rested,  the  more 
quickly  and  satisfactorily 
does  healing  occur.  Irritation 
by  biting,  nibbling,  licking, 
bandaging,  wrong  methods  of 
treatment,  and  filth  retard 
healing  and  may  result  in  serious  wound  complications.  An 
animal  in  poor  physical  condition,  or  one  kept  under  unfavor- 
able conditions  for  healing,  cannot  recover  from  the  injury 
rapidly  or  satisfactorily. 

Wound  Healing. — The  following  forms  of  healing  commonly 
occur  in  wounds :  First  and  second  intention ;  under  a  scab,  and 
by  abnormal  granulation. 


Fig.   59. — A   large  inflammatory   growth   fol- 
lowing an  injury  to  the  front  of  the  hock. 


INFLAMMATION  AND  WOUNDS  209 

Healing  by  first  intention  occurs  when  the  wound  is  clean 
cut  and  there  is  very  little  destruction  of  tissue,  and  when  there 
is  no  suppuration  or  pus  formation.  The  hlood  and  wound 
secretions  cause  the  edges  of  the  wound  to  adhere.  After  a  few 
days  or  a  week  the  union  hecomes  hrin.  Very  little  scar  tissue  is 
necessary  in  this  form  of  healing. 

Healing  by  second  intention  is  characterized  by  pus  forma- 
tion and  granulation  tissue.  After  the  first  day,  the  surface 
of  the  wound  may  be  more  or  less  covered  by  red,  granular-like 
tissue.  Later  this  granular  appearance  is  modified  by  an 
accumulation  of  creamy  pus  and  swelling  of  the  part,  and 
finally  scab  formation  and  contraction  of  the  new  scar  tissue. 

Abrasions  and  superficial  wounds  usually  heal  under  a 
scab.  The  scab  is  formed  by  the  blood  and  wound  secretions. 
This  protects  the  surface  of  the  wound  until  finally  the  de- 
stroyed tissue  is  replaced  by  the  granulations,  and  the  skin  sur- 
face is  restored. 

Abnormal  granulation  is  not  an  uncommon  form  of  healing 
in  domestic  animals.  Mechanical  and  bacterial  irritation  causes 
the  injured  tissue  to  become  swollen  and  inflamed.  In  such  a 
wound,  excessive  and  rapid  granulation  occurs,  the  new  tissue 
piling  up  over  the  cut  surfaces  and  appearing  red  and  uneven. 
This  is  termed  excessive  granulation  or  "  proud  flesh.''  This 
tissue  may  refuse  to  "  heal  over,"  or  the  scar  may  be  large, 
prominent  and  painful.  Abnormal  tissue  (horny  or  tumor- 
like) may  sometimes  form. 

Wound  Treatment. — Wounds  in  domestic  animals  are  fre- 
quently allowed  to  heal  without  special  care  or  treatment.  This 
is  unfortunate.  The  careful  and  intelligent  treatment  of  wounds 
would  greatly  decrease  the  loss  resulting  from  this  class  of 
injuries.  The  method  of  treatment  varies  in  the  different  kinds 
of  wounds. 

The  first  step  in  the  treatment  is  to  checl'  the  hemorrhage. 
Heat,  ligation,  pressure  and  torsion  are  tlie  different  methods 
14 


210  SURGICAL  DISEASES 

recommended.  Bathing  the  wound  with  hot  water  (115  °- 
120  °  F.)  is  a  satisfactory  method  of  controlling  hemorrhage 
from  small  blood-vessels.  Ligation  and  torsion  of  the  cut  end  of 
large  blood-vessels  should  be  practised.  Pressure  over  the  sur- 
face of  the  wound  is  the  most  convenient  method  of  controlling 
hemorrhage  in  most  cases.  Whenever  possible,  the  part  should 
be  bandaged  heavily  with  clean  cheese  cloth  or  muslin.  Before 
applying  the  bandage,  it  is  advisable  to  cover  the  wound  with  a 
piece  of  sterile  gauze  or  linen  that  is  well  dusted  with  boric 
acid.  Hemorrhage  from  wounds  that  cannot  be  bandaged  may  be 
temporarily  stopped  by  pressure  with  the  hand,  or,  better,  by 
packing  the  wound  with  absorbent  cotton  and  holding  this  in 
place  with  sutures.  This  should  be  left  in  place  for  a  period  of 
twelve  or  thirty-six  hours,  depending  on  the  extent  of  the  hemor- 
rhage and  character  of  the  wound. 

The  next  step  is  the  preparation  of  the  ivound  for  healing. 
The  injured  tissues  should  be  carefully  examined  for  foreign 
bodies  such  as  hair,  dirt,  gravel,  slivers  of  wood  and  nails.  The 
hair  along  the  margins  of  the  wound  should  be  trimmed,  and  all 
tissue  that  is  so  torn  and  detached  as  to  interfere  with  healing 
cut  away.  Drainage  for  the  wound  secretions  and  pus  should  be 
provided.  The  advisability  of  suturing  the  wound  depends  on 
its  character  and  location.  A  contused-lacerated  wound  should 
not  be  closed  with  sutures  unless  it  is  clean  and  shows  no  evi- 
dence of  sloughing.  A  badly  infected  wound  should  be  left  open 
unless  satisfactory  drainage  for  the  pus  and  wound  secretions 
can  be  provided.  Wounds  across  the  muscle  and  in  parts  that 
are  quite  movable  should  not  be  sutured. 

The  after-treatment  consists  in  keeping  the  animal  quiet, 
if  the  wound  is  in  a  part  that  is  quite  movable,  and  preventing 
it  from  biting,  licking  or  nibbling  the  injury.  Wounds  in  the 
region  of  the  foot  become  irritated  with  dirt  and  by  rubbing 
against  weeds  and  grass.  This  makes  it  advisable  to  keep  the 
aTiimal  in  a  clean  stall  until  healing  is  well  advanced.     Local 


INFLAMMATION  AND  WOUNDS  211 

treatment  consists  in  keeping  the  wound  clean  by  washing  the 
part  dailv,  or  twice  daily,  with  an  antiseptic  wash  that  is  non- 
irritating.  Irritating  the  new  granuhitions  may  be  avoided  by 
frequent  and  careful  cleansing  of  the  wound.  It  is  sometimes 
advisable  to  protect  the  granulating  surface  against  irritation 
by  dusting  it  over  with  a  non-irritating  antiseptic  powder,  or 
applying  a  mixture  of  carbolic  acid  one  part  and  glycerine  twelve 
parts.  After  the  wound  shows  healthy  granulations  longer 
intervals  should  lapse  between  treatments. 

In  poorly  cared  for  and  badly  infected  wounds,  the  part 
may  become  badly  swollen,  the  granulations  pile  up  and  the 
wound  refuse  to  "  heal  over."  It  may  be  advisable  in  such 
cases  to  cut  away  the  excessive  granulations  and  stop  the  hemor- 
rhage by  cauterization  with  a  red-hot  iron,  or  by  compression. 
Unhealthy  granulations  may  be  kept  down  by  applying  caustic 
occasionally. 

Abscess. — This  is  an  accumulation  of  pus  in  the  tissues. 
It  may  be  due  to  a  severe  bruise  or  contusion  that  is  followed  by 
the  infection  of  the  part  with  some  of  the  pus-producing  bacteria. 
Abscesses  occur  in  certain  infectious  diseases.  In  strangles,  the 
disease-producing  organism  may  be  carried  to  different  regions 
of  the  body  by  the  circulatory  vessels.  This  may  result  in  a 
number  of  abscesses  forming  in  the  different  body  tissues. 

The  following  forms  of  abscess  are  recognized:  hot  and 
cold,  superficial  and  deep,  simple  and  multiple.  The  hot  is  the 
acute,  and  the  cold  the  chronic  abscess.  The  terms  superficial 
and  deep  allude  to  the  relative  position  of  the  abscess,  and  sim- 
ple and  multiple  to  the  number  present. 

An  abscess  may  first  appear  as  a  hot,  painful  swelling.  If 
superficial,  the  skin  feels  tense  and  the  contents  fluctuate  when 
pressed  on.  Later  the  fever  subsides  and  when  the  abscess  is 
pressed  upon  no  pain  occurs.    Deep  abscess  may  not  fluctuate. 

The  treatment  consists  in  converting  the  abscess  into  an  open 
wound  whenever  possible.  The  incision  should  extend  to  the 
lowest  part  of  the  wall,  so  as  to  insure  complete  drainage.     A 


212  SURGICAL  DISEASES 

cold  abscess  in  the  shoulder  region  may  become  lined  by  a  layer 
of  tissues  that  retards  healing.  In  order  to  hasten  the  healing 
process,  it  may  be  necessary  to  remove  this.  Until  granulation 
is  well  advanced,  the  abscess  cavity  should  be  irrigated  daily 
with  a  one  per  cent  water  solution  of  liquor  cresolis  compositus, 

or  a  one  to  two  thousand 
water  solution  of  corrosive 
sublimate.  The  surface  of 
the  skin  in  the  region  of  the 
abscess  should  l>e  kept  clean. 
Fistulous  Withers  and 
Poll  Evil. — These  terms  are 
applied  to  swellings,  blood 
tmnors,  abscesses  and  pus 
fistula?  that  may  be  present 
in  the  region  of  the  poll  and 
withers  (Figs.  GO  and  60a). 
Pus  fistula  is  the  character- 
istic lesion  present,  and  it  is 
the  result  of  a  suppurative 
inflammation  of  the  tissues 
in  the  region.  The  abscess 
cavity  or  cavities  are  usually 
deep,  and  may  involve  the 
ligaments  and  vertebrae. 
Fig.  60.— Fistula -f '  .  t  Bruiscs  or  coutusious  are 

of  using  r:.      -.---_, 

tlie  most  common  causes. 
The  prominence  of  these  regions  predisposes  them  to  injur)-  in  the 
stable,  or  when  rolling  on  rough  or  stony  gi'ound.  Bites  and 
bruises  to  the  withers  resulting  from  other  horses  taking  hold 
of  the  region  with  the  teeth,  or  striking  the  part  against  a  hard 
surface,  are  frequent  causes. 

The  treatment  is  both  preventive  and  surgical.     All  possible 
causes  should  be  investigated.    This  is  of  special  importance  on 


S^JtW:  7JBS1A  Ve  iC- .- 


INFLAMMATION  AND  WOUNDS 


213 


premises  where  several  horses  develop  fistulous  withers  and 
poll  evil.  If  the  cause  then  becomes  known,  it  should  be  removed. 
The  surgical  treatment  consists  in  opening  up  the  different 
abscess  cavities,  providing  com- 
plete drainage  for  the  pus  and 
destroying  the  tissue  that  lines 
the  walls  of  the  cavities.  Horses 
that  are  prone  to  rub  the  region 
should  be  prevented  from  doing 
this,  as  such  irritation  retards 
healing.  Autogenous  bacterins 
should  be  used  in  addition  to  the 
surgical  treatment.  A  pus  fis- 
tula should  heal  from  the  bottom, 
and  if  the  opening  becomes 
closed,  drainage  should  be  re- 
established. The  daily  treat- 
ment is  the  same  as  recommended 
for  abscesses.  Excessive  cutting 
and  destruction  of  the  tissues 
with  caustic  preparations  result  in  scarring  and  deformity  of 
the  part.  Such  radical  lines  of  treatment  should  be  discour- 
aged. We  should  not  delay  the  surgical  treatment  of  abscesses 
in  the  regions  of  the  poll  and  withers. 


Fig.  60a. — Fi.stula  of  the  region  of  the 
poll  of  the  head. 


QUESTIONS 

1.  Name  and  describe  the  different  forms  of  inflammation. 

2.  Give  the  causes  and  treatment  of  inflammation. 

3.  Name  and  describe  the  different  methods  by  wliich  wounds  heal. 

4.  Describe  the  treatment  of  wounds, 

5.  What  are  the  causes  of  an  abscess?     Give  the  treatment. 

6.  What  are  the  causes  of  fistula  and  poll  evil?    Give  the  treatment. 


CHAPTER  XXII 
FRACTURES  AND  HARNESS  INJURIES 

Fractures, — Broken  bones  or  fractures  are  not  uncommon 
in  domestic  animals.  In  the  horse,  the  bones  of  the  leg,  forearm, 
foot,  and  spine  are  the  most  commonly  broken.  In  the  dog  the 
largest  percentage  of  fractures  occurs  in  the  superior  regions 
of  the  limbs. 

Fractures  may  be  classified  as  simple  and  compound,  com- 
plete and  incomplete,  comminuted  or  splinter.  In  the  simple 
fracture  the  skin  over  the  region  escapes  injury,  but  in  the  com- 
pound fracture  the  skin  is  broken  and  the  ends  of  the  broken 
bone  may  protrude  through  it.  The  terms  complete  and  in- 
complete are  used  in  describing  fractures  in  which  the  ends  of 
the  bones  are  not  attached  to  each  other,  or  partially  so.  In  the 
comminuted  fracture  the  bone  is  broken  into  a  number  of  pieces. 
There  are  a  number  of  other  terms  that  may  be  used  in  designat- 
ing the  different  kinds  of  fractures,  svich  as  double,  when  both 
bones  in  the  region  are  broken,  and  oblique,  transverse  and 
longitudinal,  depending  on  the  direction  of  the  break. 

The  causes  of  fractures  may  be  divided  into  external  or 
mechanical,  and  internal.  Fractures  may  result  from  kicks, 
blows,  muscular  strain  and  contusions.  Abnormal  fragility  due 
to  disease,  extreme  youth  and  old  age  are  the  internal  predis- 
posing factors. 

The  sympto7ns  are  crepitation,  abnormal  movement  and  de- 
formity of  tho  part.  Abnormal  movement  of  the  part  and 
inability  to  support  weight  occur  in  fractures  of  the  bones  of 
the  limbs.  (Crepitation  or  a  grinding,  rubbing  sound  due  to  the 
movement  of  the  ends  of  tho  broken  bones  on  one  another  occurs 
when  the  part  is  moved  or  manipulated  with  the  hands.  Pain, 
swelling  and  injury  to  the  skin  are  other  local  symptoms.  The 
214 


FRACTURES  AND  HARNESS  INJURIES  215 

new  tissue  or  bone  callus  is  formed  bv  the  bone-forming  cells 
in  the  deeper  layer  of  the  periosteum  and  bone-marrow. 

The  prognosis  is  unfavorable.  The  larger  percentage  of 
fractures  in  domestic  animals  are  incurable,  or  make  an  un- 
satisfactory recovery.  This  is  due  to  careless  treatment,  the 
character  of  the  fracture  and  the  inability  to  fix  the  ends  of  the 
broken  bone.  Fractures  in  young  and  small  animals  usually 
heal  quickly.  Individuals  that  are  healthy  and  vigorous  usually 
make  a  speedy  recovery.  Fractures  heal  very  slowly  in  the  aged. 
Compound  and  comminuted  fractures  are  impossible  to  treat 
in  the  larger  percentage  of  cases. 

The  treatment  consists  in  fixing  the  broken  bone  or  bones 
in  a  normal  position  by  means  of  bandages  and  splints.  If 
this  is  not  practised,  the  surrounding  tissues  become  injured  by 
the  broken  ends  of  the  bone,  and  the  fracture  may  become  so 
complicated  as  to  render  treatment  useless.  Motion  retards  or 
prevents  the  repair  of  the  break. 

However,  fractures  of  the  ribs,  pelvic  bones  and  sometimes 
long  bones  that  are  well  covered  by  heavy  muscles  heal  naturally 
or  in  the  absence  of  any  means  of  retention. 

Bandaging. — The  attendant  must  use  good  judgment  in  de- 
vising means  of  fixing  the  broken  bone,  and  in  holding  it  in  its 
natural  position.  Whenever  possible,  a  plaster  bandage  should 
be  used.  This  must  not  be  made  too  heavy,  and  it  is  very  neces- 
sary to  adjust  it  properly,  so  that  it  will  stay  in  place  and  not 
become  too  tight  or  too  loose.  When  applied  to  the  limb,  the 
bandage  should  extend  as  far  down  as  the  hoof,  and  some  dis- 
tance above  the  break.  This  is  necessary  in  order  to  keep  it  from 
slipping  down  and  becoming  too  loose.  A  soft  bandage  should 
be  applied  first  in  order  to  equalize  the  pressure  from  the  plaster 
cast  and  protect  the  skin.  Wooden  splints  are  not  very  satis- 
factory agents  for  the  treatment  of  fractures.  Thick  leather  that 
has  been  made  soft  by  soaking  in  warm  water  and  then  shaping 
it  to  the  part  makes  a  more  satisfactory  splint.     In  all  cases  a 


216 


SURGICAL  DISEASES 


soft  bandage  should  be  applied  under  the  splint.  The  adjust- 
ment of  the  plaster  bandage  or  splint  should  be  noticed  daily,  and 
whenever  necessary  it  should  be  removed  and  readjusted 

Injuries  to  the  skin  must  be  carefully  cleaned,  disinfected 
and  bandaged  before  applying  the  plaster  bandage.  If  evidence 
of  wound  infection  occurs  later,  the  bandage  must  be  removed 
and  the  wound  treated.  Large  animals  suffering  with  a  fracture 
of  any  of  the  bones  of  the  limb  should  be  placed  in  slings.  In- 
complete fracture  should  receive  the  same  treatment  as  simple 


Fig.   61. — Shoulder  abscess  caused  by  loose-fitting  harness. 

fracture.  If  this  is  practised,  the  danger  of  its  becoming  com- 
plete is  avoided. 

Harness  Injuries. — This  class  of  injuries  is  common  in 
horses  that  are  given  steady,  hard  work,  or  that  are  not  accus- 
tomed to  work.  Young  horses,  when  first  put  to  hard  work,  are 
especially  prone  to  injuries  from  the  collar.  A  large  proportion 
of  these  injuries  are  due  to  an  ill-fitting  harness  or  saddle. 

When  the  harness  is  not  adjusted  or  fitted  properly,  there  is 
severe  pressure  on  certain  parts.  This  is  the  common  cause  of 
shoulder  abscesses  (Fig.  61),  sore  necks  and  sit-fasts.     Kough, 


FRACTURES  AND  HARNESS  INJURIES  217 

uneven  surfaces  on  the  faces  of  the  collar  and  saddle  are  the 
common  causes  of  galling.  The  character  of  the  work  is  an 
important  factor.  Work  that  requires  the  animal  to  support 
weight  on  the  top  surface  of  the  neck  is  productive  of  sore  neck. 
Heavy  work  over  rough,  uneven  ground  frequently  causes 
shoulder  abscesses  and  strained  muscles. 

The  simplest  and  most  common  harness  injuries  are  galling, 
sore  shoulders  and  sore  neck.  Harness  galls  first  appear  as  flat, 
painful  swellings.  On  raising  the  collar  from  the  skin  the  in- 
flamed area  appears  dry  and  the  surrounding  hair  is  wet  with 
sweat.  Later,  the  skin  becomes  hard  and  its  outer  layer,  and 
sometimes  the  deeper  layer  as  well,  slough,  or  is  rubbed  off  by 
friction  of  the  harness.  The  surface  then  appears  red  and 
moist.  Fluctuating  swellings  due  to  small  collections  of  blood 
and  l}Tnph  sometimes  form.  Sometimes,  small  areas  on  the  face 
of  the  shoulder  and  that  portion  of  the  back  pressed  on  by  the 
saddle  become  swollen,  indurated  and  hard  and  give  the  shoulder 
a  rough  appearance.  Continuous  irritation  from  the  collar  may 
cause  an  inflammatory  thickening  of  the  subcutaneous  tissue  in 
the  shoulder  region,  and  the  skin  appears  loose  and  somewhat 
folded.    This  uneven  surface  is  productive  of  chronic  collar  galls. 

A  sit-fast  is  characterized  by  a  large  swelling  at  the  top  of 
the  neck,  followed  by  a  deep  sloughing  of  the  tissues.  A  slightly 
swollen,  wrinkled  condition  of  the  skin  over  the  top  of  the  neck 
is  sometimes  present  in  horses  that  resist  the  attendant,  when 
he  attempts  to  handle  the  part  or  harness  the  animal.  This  form 
of  sore  neck  is  evidently  very  painful,  although  little  evidence 
of  inflammation  is  present. 

Strain  of  shoulder  muscles  and  shoulder  abscesses  have  been 
discussed  under  their  separate  heads. 

The  treatment  is  very  largely  preventive.  Too  little  atten- 
tion is  given  to' the  proper  fitting  of  the  harness  and  saddle.  A 
well-fitted  collar  that  properly  distributes  the  weight  on  the 
shoulder,  and  is  neither  too  small  or  too  large  at  the  top  of  the 


218  SURGICAL  DISEASES 

neck,  is  the  best  preventive  for  shoulder  and  neck  injuries.  Old, 
ill-fitting,  lumpy  collars  should  not  be  used.  Neither  should  the 
same  collar  be  used  for  different  horses.  Farmers  should  avoid 
using  sweat  pads  that  are  lumpy  or  soaked  with  sweat.  If  soft 
and  dry,  such  pads  are  useful  in  preventing  galling.  The  sur- 
faces of  the  collar  or  saddle  that  come  in  contact  with  the  skin 
should  be  kept  smooth  and  clean.  In  the  spring  of  the  year,  it  is 
advisable  to  bathe  the  shoulders  of  work  horses  with  cold  water 
twice  a  day.  Bathing  the  shoulders  with  the  following  prepara- 
tion is  a  useful  preventive  measure :  lead  acetate  four  ounces, 
zinc  sulfate  three  ounces  and  water  one  gallon.  Smooth  leather 
pads  for  the  top  of  the  collar  and  saddle  are  useful  preventive 
and  curative  agents. 

Galls  are  best  treated  by  rest.  Ointments  or  "  gall  cures  " 
are  usually  applied.  The  following  dry  dressing  dusted  over  the 
red,  moist,  abraded  surfaces  is  quite  healing:  tannic  acid  one 
ounce,  boric  acid  four  ounces,  and  calomel  two  ounces.  This 
may  be  dusted  over  the  part  two  or  three  times  daily.  Dry, 
abraded  surfaces  may  be  treated  by  applying  a  mixture  of 
glycerine  four  ounces,  tannic  acid  one-half  ounce  and  carbolic 
acid  one  dram.  In  operating  for  the  removal  of  fibrous  enlarge- 
ments, thickened  skin  and  abscesses  on  the  front  of  the  shoulder, 
it  is  advisable  to  make  the  incision  in  the  skin  well  to  the  side  of 
the  face  of  the  shoulder  in  order  to  avoid  scarring  the  surface 
that  comes  in  contact  with  the  collar. 

QUESTIONS 

1.  Name  and  describe  the  difTereiit  kinds  of  fractures. 

2.  What  are  the  symptoms  of  fracture? 

3.  Describe  the  treatment  of  fractures. 

4.  Wliat  are  the  causes  of  harness  injuries? 

5.  Describe  the  treatment  of  the  different  liarncss  injuries. 


CHAPTER  XXIII 

COMMON  SURGICAL  OPERATIONS 

Dehorning  Cattle. — It  is  very  often  necessary  to  remove  the 
horns  of  cattle  in  order  to  prevent  their  injuring  or  worrying 
certain  individuals  in  the  herd.  This  operation  is  of  greatest 
economic  importance  in  dairy  and  feeding  cattle.  When  first 
practised,  the  dehorning  of  mature  cattle  was  condemned  by 
some  persons  who  deemed  it  an  inhuman  and  unnecessary  opera- 
tion. It  is  surely  a  humane  act  to  remove  the  horns  of  cattle  that 
are  confined  in  small  yards  and  pastures,  and  prevent  them  from 
painfully,  or  seriously,  injuring  one  another. 

In  most  localities  there  are  men  who  are  well  equipped  to 
dehorn  cattle,  and  able  to  perform  this  operation  for  a  very 
moderate  fee.  It  is  not  advisable  to  attempt  to  dehorn  a  number 
of  adult  cattle  if  the  operator  is  not  well  equipped  for  the  work. 
Unless  a  well-con stnicted  dehorning  rack  is  available  for  con- 
fining the  animals,  there  is  danger  of  injuring  them  and  it  is 
very  difficult  to  saw  off  the  horn  quickly  and  satisfactorily. 
This  increases  the  pain  that  the  animal  suffers,  and  horn  stubs 
soon  develop. 

Good  equipment,  such  as  a  chute,  saw  or  clippers,  is  neces- 
sary. A  dehorning  chute  should  be  built  of  plank  with  a  good 
frame  well  bolted  together,  with  stanchion  and  nose  block  for 
confining  the  head.  Most  operators  prefer  a  meat  saw  for  cutting 
off  the  horns.  It  is  preferable  to  dehorning  shears,  as  there  is 
danger  of  fracturing  the  frontal  bone  when  removing  the  horns 
of  mature  cattle.  The  best  form  of  dehorning  shears  have  a 
wide  V  in  the  cutting  edge. 

The  operation  is  very  simple.  The  horn  should  be  cut  off 
at  a  point  from  one-quarter  to  one-half  an  inch  below  the  hair 
line  or  skin.    If  this  is  not  practised,  an  irregiilar  horn  growth 

219 


220  SURGICAL  DISEASES 

or  stub  of  bom  develops.  It  is  usually  unnecessary  to  apply 
auytbing  to  tbe  wound.  If  tbe  animal  does  not  strike  or  rub 
the  part,  the  clot  that  forms  closes  the  blood-vessels  and  the 
hemorrhage  stops.  In  case  of  hemorrhage  of  a  serious  nature, 
a  small  piece  of  absorbent  cotton  may  be  spread  over  the  sur- 
face of  the  wound,  and  pushed  in  to  the  opening  in  order  to  keep 
it  in  place.  Pine  tar  may  be  smeared  over  this  dressing.  Some 
operators  prefer  cauterizing  the  wound  with  a  red-hot  iron  for 
the  purpose  of  preventing  hemorrhage.  During  warm  weather, 
the  wound  should  be  washed  daily  with  a  two  per  cent  water 
solution  of  a  coal  tar  disinfectant,  until  healing  is  well  advanced. 
A  very  necessary  after-treatment  is  the  washing  of  the  part  after 
two  or  three  days  for  the  purpose  of  removing  the  dried  blood. 

The  opening  at  the  base  of  the  horn  communicates  directly 
with  the  frontal  sinus,  a  large  cavity  situated  between  the  two 
plates  of  the  frontal  bone.  Sometimes  the  bone  is  slivered,  or 
the  wound  becomes  infected  and  inflamed.  This  may  be  due  to  a 
dirty  dehorning  saw,  or  getting  dirt  into  the  wound.  The  in- 
flammation may  extend  to  the  sinus  and  a  heavy  discharge  from 
the  cavity  occur.  This  complication  may  be  prevented  by  plac- 
ing the  saw  or  cutters  in  a  disinfectant  when  not  in  use,  and 
cleaning  and  disinfecting  the  wound  very  carefully  for  a  few 
days  after  the  operation. 

The  horn  buttons  of  calves  from  a  few  days  to  one  week  of 
age  can  be  destroyed,  and  the  growth  of  the  horn  prevented  by 
applying  caustic  soda  or  potash  to  them.  The  method  of  pro- 
cedure is  as  follows :  Clip  away  the  hair  from  around  the  base 
of  the  horn  tissue  and  apply  a  little  vaseline  to  the  skin  near,- 
but  not  close  to,  the  base  of  the  horn ;  moisten  the  horn  button 
and  rub  it  two  or  three  times  with  the  end  of  the  stick  of  caustic ; 
do  not  allow  the  calf  to  go  out  in  the  rain  for  a  few  days  after 
applying  the  caustic.  The  horns  of  calves  a  few  weeks  of  age 
may  be  removed  with  a  sharp  knife  or  calf  dehorner. 

Choking. — This  is  a  common  accident  in  cattle  and  horses. 


COMMON  SURGICAL  OPERATIONS  221 

The  object  that  causes  the  choke  may  he  lodged  in  the  pharynx 
or  oesophagiis.  Certain  individuals  are  more  prone  to  choke 
while  feeding  than  others.  This  is  because  of  their  habit  of 
eating  greedily,  and  swallowing  hastily  without  properly  mixing 
the  bolus  with  the  saliva.  For  this  reason,  choking  occurs  when 
the  animal  is  eating  dry  feed.  Cattle  frequently  become  choked 
on  pieces  of  such  food  as  roots  and  apples  that  are  t^o  large  to 
readily  pass  down  the  oesophagus.  Sharp  objects  taken  in  with 
the  food  sometimes  become  lodged  in  the  cesophagTis  or  pharynx. 

The  symptoms  differ  in  complete  and  partial  choke.  In  the 
latter,  the  symptoms  are  not  very  characteristic.  The  animal 
may  stop  feeding,  but  shows  very  little  evidence  of  suffering 
pain.  It  may  be  able  to  swallow  a  little  water.  On  attempting 
to  drink,  a  part  of  the  water  may  be  returned  through  the  nose, 
the  same  as  in  complete  choke.  Ineffectual  eft'oits  to  swallow, 
salivation,  coughing,  hurried  respiration,  and  an  anxious  ex- 
pression of  the  face  occur  in  complete  choke.  Bloating  may 
complicate  this  accident  in  ruminants.  After  partial  choke  has 
persisted  for  a  day  or  two,  the  animal  appears  dejected  or  dis- 
tressed. Pressure  on  the  trachea  by  hard  objects  may  cause 
difficult  respiration. 

Mechanical  pneumonia  sometimes  occurs.  This  is  due  to 
the  food  and  water  that  the  animal  may  attempt  to  swallow, 
being  returned  to  the  pharynx  and  passed  into  the  air  passages 
and  lungs. 

The  treatment  is  as  follows:  Animals  that  have  choked 
should  not  be  given  access  to  feed  of  any  kind.  Any  attempt  to 
take  food  or  drink  water  may  result  in  pneumonia.  It  may  be 
necessary  to  drench  the  animal  with  a  very  small  quantity  of 
water  for  the  purpose  of  diag-nosis.  The  most  common  form  of 
choke  in  horses  is  that  due  to  accumulation  of  dry  food  in  the 
oesophagus.  The  administration  of  a  dnig  that  stimulates  the 
secretion  of  saliva  is  a  very  successful  method  of  relieving  this 
form  of  choke.    Pilocarpine  is  the  drug  commonly  used.    Cheap 


222  SURGICAL  DISEASES 

whips  should  not  be  introduced  into  the  oesophagus  for  the  pur- 
pose of  dislodging  the  foreign  body.  There  is  always  danger  of 
the  whip  becoming  broken  off,  and  the  broken  part  lodging  in  the 
opsophagus.  Neither  should  such  rigid  objects  as  a  broom  or 
rake  handle  be  introduced,  because  of  the  danger  from  serious 
injury  to  the  walls  of  the  pharynx  and  oesophagus.  The  flexible 
probang,  which  is  usually  made  of  spiral  wire  covered  with 
leather,  is  a  very  useful  instrument  to  relieve  choke  when  in  the 
hands  of  an  experienced  operator.  If  the  object  causing  the 
choke  is  situated  in  the  neck  portion  of  the  oesophagus,  it  may 
sometimes  be  moved  forward,  or  toward  the  stomach  by  pressure 
with  the  fingers. 

Castration. — The  castration  of  the  male  is  a  common  opera- 
tion in  domestic  animals.  The  purpose  of  the  operation  is  to 
render  the  animal  more  useful  for  work  or  meat  production. 

The  age  at  which  the  operation  is  performed  varies  in  the 
different  species.  The  colt  is  usually  castrated  when  he  is  one 
year  old,  and  the  calf,  pig  and  lamb  when  a  few  weeks  or  a  few 
months  of  age.  It  is  not  advisable  to  castrate  the  young  at  wean- 
ing time.  The  operation  and  the  weaning  together  may  tempo- 
rarily check  the  growth  of  the  animal.  Colts  that  are  unde- 
veloped and  in  poor  flesh,  or  affected  with  colt  distemper,  should 
be  allowed  to  recover  before  they  are  operated  on.  In  all  ani- 
mals, it  is  advisable  to  wait  until  after  they  have  recovered 
from  disease  and  become  thrifty  and  strong. 

The  spring,  early  summer  and  fall  are  the  most  suitable 
seasons  for  castrating  the  young.  It  may  be  practised  during  the 
hot  or  cold  months  of  the  year  with  little  danger  from  wound 
infection  or  other  complications,  providing  the  necessary  after- 
attention  can  be  given. 

The  preparation  of  the  animal  for  the  operation  by  with- 
holding all  feed  for  about  twelve  hours  is  very  advisable.  If 
this  is  practised,  the  stomach  and  intestines  are  not  distended 
with  feed,  and  the  young  are  cleaner,  easier  to  handle  and  suffer 


V^ 


COMMON  SURGICAL  OPERATIONS  223 

less  from  castration.  Clean  quarters  and  surroundings  are  very 
necessary  to  the  success  of  the  operation. 

The  instruments  required  are  sharp  knives,  preferably  a 
heavy  scalpel  and  a  probe-pointed  bistoury,  an  emasculator  for 
large  and  mature  animals,  and  surgeon's  needles  and  sutjre 
material.  Eopes  and  casting  harness  are  frequently  used  for 
confining  and  casting  the  large  and  mature  animals.  Two 
clean  pans  or  pails  tilled  with  a  two  per  cent  water  solution  of 
liquor  cresolis  compositus,  or  an  equally  reliable  disinfectant, 
should  be  provided  for  cleaning  the  scrotum  and  neighboring 
parts  and  the  instruments.  Pieces  of  absorbent  cotton  or  oakum 
may  be  used  in  washing  and  cleaning  the  scrotum.  The  instru- 
ments should  be  sterilized  in  boiling  water  before  using. 

//  a  number  of  pigs  or  lambs  are  to  be  castrated,  it  is  best 
to  confine  them  in  a  small,  clean,  well-bedded  pen.  This  enables 
the  attendant  to  catch  them  quickly  and  without  unnecessary 
excitement  or  exercise.  They  should  be  taken  to  an  adjoining 
pen  to  be  castrated.  The  scrotum  should  be  w^ashed  with  the 
disinfectant,  and  the  testicles  pressed  tightly  against  the  scrotal 
wall.  An  incision  parallel  with  the  middle  line  or  raphe  and  a 
little  to  one  side  is  made  through  the  skin  and  the  coverings  of 
the  testicle,  and  the  testicle  pressed  out  through  the  incision. 
The  testicle  and  cords  are  then  jjulled  well  out  and  the  cord 
broken  off  with  a  quick  jerk  and  twist,  or  scraped  off  with  a 
knife.  The  latter  method  is  to  be  preferred  in  large  lambs  if 
the  operator  does  not  have  an  emasculator.  The  incision  in  the 
scrotum  should  be  extended  from  its  base  to  the  lowest  part,  in 
order  to  secure  perfect  drainage. 

Young  calves  may  be  castrated  in  the  standing  position  or 
when  cast  and  held  on  the  side.  The  method  of  operating  is  the 
same  as  recommended  for  pigs  and  lambs. 

The  castration  of  the  colt  may  be  performed  in  either  the 
standing  position  or  w^hen  cast.  The  method  of  operating  is 
the  same  as  practised  in  the  smaller  animals  with  the  exception 


224  SURGICAL  DISEASES 

of  cutting  off  the  cord.  The  emasculator  is  used  here.  This 
instrument  crushes  the  stump  of  the  cord  and  prevents  hemor- 
rhage from  the  cut  ends  of  the  blood-vessels.  Careful  aseptic 
precautions  must  be  observed  in  operating  on  colts,  as  they  are 
very  susceptible  to  wound  infection  and  peritonitis. 

The  blood-vessels  of  the  testicular  cord  are  larger  in  the  adult 
animals,  and  the  danger  from  hemorrhage  is  greater  than  in  the 
young.  For  this  reason,  it  is  advisable  to  use  an  emasculator 
in  castrating  all  mature  animals. 

Complications  Following  Castration. — The  hemorrhage 
from  the  wound  and  stump  of  cord  is  usually  unimportant  in 
the  young  animals.  Serious  hemorrhage  from  the  vessels  of 
the  cord  sometimes  occur  in  the  adult,  and  a  persistent  hemor- 
rhage results  when  a  subcutaneous  vein  is  cut  in  making  the  in- 
cision in  the  scrotum.  This  complication  is  not  usually  serious, 
and  can  be  prevented  and  controlled  by  observing  proper  pre- 
cautions in  cutting  off  the  cord,  or  by  picking  up  the  cut  ends  of 
the  vessel  and  ligating  it.  Packing  the  scrotal  sack  with  sterile 
gauze  or  absorbent  cotton,  and  closing  the  incision  with  sutures 
may  be  practised  for  the  purpose  of  stopping  this  form  of 
hemorrhage.  The  packing  should  be  removed  in  about  twelve 
hours. 

The  infection  of  the  wound  always  follows  castration.  If 
the  incision  is  small  and  the  operation  is  followed  by  swelling 
of  the  neighboring  tissues,  the  clotted  blood,  wound  secretions 
and  pus  become  penned  up  in  the  scrotal  sack.  Local  blood 
poisoning  or  peritonitis  follows.  This  is  not  an  uncommon 
complication.  It  can  be  prevented  by  aseptic  precautions  in 
operating,  and  insuring  good  drainage  by  extending  the  incision 
to  the  lowest  part  of  the  scrotal  sac.  The  scrotal  sac  always 
contracts  down  and  becomes  more  or  less  swollen  within  a  day  or 
two  following  castration.  We  must  keep  this  in  mind  when 
enlarging  the  opening,  and  be  sure  and  make  it  plenty  large  to 
permit  the  escape  of  the  infectious  matter.    In  castrating  sheep, 


COMMON  SURGICAL  OPERATIONS  225 

all  wool  in  the  region  of  the  scrotal  sac  should  be  clipped  off, 
as  this  interferes  with  drainage  from  the  wound. 

Exercise  foUowing  castration  is  almost  as  essential  as  clean 
quarters.  Lack  of  exercise  leads  to  opclematous  swelling  in  the 
region  of  the  scrotum,  and  the  lips  of  the  incision  may  become 
adhered  if  the  animal  is  at  rest.  Colts  and  all  mature  animals 
that  are  confined  in  close  quarters  should  be  examined  within 
forty-eight  hours  following  the  operation,  and  the  condition  of 
the  wound  noted.  If  closed,  the  hands  should  be  cleaned  and  dis- 
infected, and  the  adhesion  broken  down  with  the  fingers.  It  is 
best  to  exercise  horses  daily. 

It  is  unsafe  to  expose  castrated  animals  to  cold,  damp,  chilly 
weather.  The  shock  and  soreness  resulting  from  the  operation 
render  the  animal  highly  susceptible  to  pleurisy  and  pneumonia. 
This  is  especially  true  of  young  colts. 

Inguinal  hernia  or '"  rupture  "  may  complicate  the  operation. 
This  fonn  of  hernia  is  quite  frequently  met  with  in  pigs,  and 
only  occasionally  in  the  other  animals.  This  complication  is 
usually  overcome  by  practising  what  is  commonly  termed  the 
covered  operation.  The  pig  is  usually  held  or  hung  up  by  the 
hind  legs.  A  larger  animal  is  placed  on  its  back.  The  hernia 
is  reduced  by  manipulating  the  mass  of  intestines  with  the 
fingers,  so  that  they  drop  back  into  the  abdominal  cavity.  The 
part  is  carefully  cleaned  and  disinfected  and  an  incision  made 
through  the  scrotal  wall,  and  the  thin  covering  or  serous  sac 
in  which  the  testicle  is  lodged  is  exposed.  The  testicle  with  the 
cord  and  covering  is  drawn  well  out  of  the  scrotum  and  held  by 
an  attendant.  The  operator  then  passes  a  needle  carrying  a 
strong  silk  thread  through  the  cord  and  covering,  below  the 
point  where  he  intends  severing  it.  The  needle  is  removed  and 
the  cord  and  covering  ligated  at  this  point.  The  cord  is  then 
cut  off  about  one-half  an  inch  from  the  ligature,  and  the  incision 
in  the  scrotum  made  plenty  large  in  order  to  insure  drainage. 
It  is  very  essential  to  the  success  of  this  operation  that  the 
15 


226  SURGICAL  DISEASES 

animal  be  dieted  for  twelve  or  eighteen  hours  before  attempting 
to  operate.  The  after-treatment  consists  in  giving  the  animal 
separate  quarters  and  feeding  a  light  diet. 

Enlarged  or  scirrhous  cords  follow  infection  of  the  wound, 
usually  with  spores  of  a  certain  fungus  (Botryomyces).  This 
complication  more  often  follows  castration  of  cattle  and  pigs 
than  of  colts.  Wrong  methods  of  operating,  such  as  leaving  the 
stump  of  the  cord  too  long  and  insufficient  drainage  for  the  pus 
and  wound  secretions,  are  tlie  factors  that  favor  this  complica- 
tion. Scirrhous  cords  or  fibrous  tumors  should  be  dissected 
out  and  removed  before  they  have  become  large  and  begun 
breaking  do^vn. 

Castration  of  Ridgeling  or  Cryptorchid  Animals. — In  the 
ridgeling  animal  one  or  both  of  the  testicles  have  not  descended 
into  the  scrotal  sac,  and  are  usually  lodged  in  the  inguinal 
canal  or  abdominal  cavity.  If  the  testicle  is  lodged  in  the 
inguinal  canal  the  animal  is  tenned  a  "  flanker."  In  yearling 
colts  the  testicular  cord  is  sometimes  short,  and  the  testicle  is 
situated  high  up  in  the  scrotum  and  inguinal  canal.  In  examin- 
ing a  supposed  cryptorchid  colt,  he  should  be  twitched.  This  may 
cause  the  testicle  to  descend  into  the  scrotum. 

The  castration  of  a  true  cryptorchid  requires  a  special  opera- 
tion. When  properly  performed  and  the  animal  given  special 
after-care,  the  operation  is  not  followed  by  any  serious  complica- 
tions. An  abnormally  large,  diseased  testicle  is  sometimes  met 
with  that  cannot  be  removed  in  the  usual  way,  and  which  com- 
plicates and  increases  the  difficulty  of  operating. 

Caponizing. — The  castration  or  caponizing  of  the  male 
chicken  is  commonly  practised  in  certain  localities.  This  opera- 
tion changes  the  disposition  of  the  cockerel.  He  becomes  more 
quiet  and  sluggish,  never  crows,  the  head  is  small,  the  comb  and 
wattles  cease  growing  and  the  hackle  and  saddle  feathers  become 
well  developed.  A  capon  always  develops  more  uniformly  and 
is  larger  than  the  cockerel. 


COMMON  SURGICAL  OPERATIONS  227 

The  hest  time  to  caponize  the  cockerel  is  when  he  weighs 
between  two  or  three  pounds.  If  older  and  heavier,  the  testicle 
becomes  so  large  that  it  is  very  difficult  to  remove,  and  the  danger 
from  tearing  the  spermatic  artery  and  a  fatal  hemorrhage  result- 
ing is  greater. 

There  are  several  kinds  of  caponizing  instruments.  They 
may  be  purchased  in  sets.  Each  set  should  contain  an  instru- 
ment for  removing  the  testicle ;  a  knife  for  making  the  incision 
through  the  abdominal  wall ;  a  sharp  hook  for  tearing  through 
the  thin  membrane ;  spring  spreader  for  holding  the  lips  of  the 
incision  apart;  a  blunt  probe  for  keeping  the  intestines  out  of 
the  way  of  the  operator;  and  a  pair  of  tweezers  for  removing 
clots  of  blood.  The  different  instniments  for  removing  the 
testicles  are  a  spoon-like  scoop,  spoon  forceps  and  cannula.  The 
spoon-like  scoop  is  preferred  by  most  operators. 

The  cockerel  is  confined  for  the  operation  by  passing  a  strong 
noose  of  cord  around  both  legs,  and  a  second  noose  around  the 
wings  close  to  the  body,  that  have  weights  fastened  to  them. 
The  cords  pass  through  holes  or  loops  in  a  barrel  or  board  tliat 
is  used  for  an  operating  table.  This  holds  the  cockerel  firmly 
and  prevents  his  struggling. 

The  bird  should  he  prepared  for  the  operation  by  withhold- 
ing all  feed  and  water  for  a  period  of  twenty-four  hours  or  longer, 
for  the  purpose  of  emptying  out  the  intestine.  The  operator 
must  have  a  strong  light,  in  order  to  work  quickly  and  safely. 
Direct  sunlight  or  electric  light  should  be  used. 

The  instruments  should  be  placed  in  a  two  per  cent  water 
solution  of  carbolic  acid.  A  second  vessel  containing  a  two  per 
cent  water  solution  of  liquor  cresolis  compound  for  cleaning 
the  skin  is  necessary.  Absorbent  cotton  should  be  used  for 
washing  the  wound. 

The  general  method  of  operating  is  as  follows :  The  incision 
is  made  between  the  last  two  ribs  and  in  front  of  the  thigh. 


228  SURGICAL  DISEASES 

The  feathers  over  this  region  should  be  removed,  and  the  skin 
j)ul]ed  to  one  side  before  making  the  incision.  An  incision  about 
one  and  one-half  inches  in  leng-th  is  made  through  the  skin  and 
muscles,  and  the  spreader  inserted.  The  sharp  hook  is  then 
inserted  and  the  thin  serous  membrane  over  the  intestine  is  torn 
through.  The  testicles  are  situated  in  the  superior  portion  of 
the  abdominal  cavity  or  under  the  back.  On  pushing  the  intes- 
tines to  one  side,  both  testicles,  which  are  about  the  size  of  a  bean 
and  yellowish  in  color,  can  be  seen.  The  lower  one  should  be  re- 
moved first.  After  removing  both  testicles,  blood  clots,  feathers, 
or  any  foreign  body  that  may  have  gotten  into  the  wound  should 
be  picked  up  with  the  tweezers  before  removing  the  spreaders 
and  allowing  the  wound  to  close.  N^o  special  after-treatment  is 
required. 

The  most  common  complication  is  rupture  of  the  spermatic 
artery.  This  occurs  at  the  time  the  testicle  is  torn  loose  and  may 
be  due  to  careless  methods,  or  operating  on  cockerels  that  are 
too  large.  If  all  of  the  testicle  is  not  removed  from  the  abdominal 
cavity,  the  bird  is  termed  a  "  slip."  Sometimes  air  puffs  form 
after  the  operation.  These  should  be  punctured  with  a  sharp 
knife. 

Ovariotomy,  "  Spaying." — The  removal  of  the  ovaries,  or 
ovariotomy,  is  practised  for  the  purpose  of  rendering  the  female 
more  useful  for  meat  production,  j^rolonging  the  period  of 
lactation,  overcoming  vicious  habits  and  preventing  oestrum  or 
heat  The  operation  is  commonly  performed  in  the  heifer  and 
bitch,  occasionally  in  the  mare,  and  at  present  rarely  in  the  sow. 

Heifers  are  usually  spayed  between  the  ages  of  eight  and 
twelve  months;  the  bitch  and  sow  when  a  few  months  old,  or 
before  the  periods  of  heat  have  begun.  The  mare  is  spayed 
when  mature.  It  is'  possible  to  spay  the  female  at  any  age,  but 
the  ages  mentioned  are  the  most  convenient.  Pregnant  animals 
should  not  be  operated  on.     The  season  of  the  year  makes  little 


COMMON  SURGICAL  OPERATIONS  229 

difference  in  the  results,  providing  the  animal  can  be  kept  under 
close  observation  and  given  the  necessary  care  and  treatment. 
The  spring  of  the  year,  just  before  turning  the  herd  on  pasture, 
is  the  best  season  to  spay  heifers. 

All  animals  should  he  prepared  for  the  operation  by  with- 
holding all  feed  for  at  least  twenty-four  hours  before  they 
are  operated  on,  and  it  may  be  advisable  to  give  them  a  physic. 
It  is  easier  to  operate  when  the  intestinal  tract  is  comparatively 
empty,  and  the  death  rate  is  lower  than  when  the  animal  is  not 
properly  prepared  for  the  operation. 

The  method  of  operaUng  is  not  the  same  in  the  different 
species.  In  young  heifers  and  sows,  the  flank  operation  is  pre- 
ferred, and  in  mares  and  cows,  the  vaginal  operation.  The 
median  line  operation  is  practised  in  bitches.  A  spaying  emascu- 
lator,  or  ecraseur,  are  the  special  instruments  uoed  for  removing 
the  ovaries. 

The  animal  must  be  properly  confined  for  the  operation. 
Heifers  are  usually  held  in  the  standing  position  by  fastening 
the  head  securely,  and  crowding  the  left  side  of  the  animal 
against  a  solid  board  partition,  or  side  of  a  chute.  If  the  vaginal 
operation  is  performed,  the  mare  or  cow  may  be  confined  in 
stocks.  The  bitch  is  usually  anesthetized  and  placed  on  her 
back  on  a  table  that  is  inclined,  so  that  the  hind  parts  are 
elevated. 

Ovariotomy  cannot  be  successfully  performed  by  an  un- 
trained and  inexperienced  operator.  The  necessary  precautions 
acainst  the  infection  of  the  part  must  be  observed,  in  order  to 
promote  the  healing  of  the  wound  and  prevent  peritonitis.  The 
seat  of  the  operation  should  be  carefully  cleaned  and  disinfected. 

Following  tJte  operation  the  animal  should  be  fed  a  spare 
diet  for  a  few  days.  This  is  a  very  necessary  part  of  the  care 
of  the  bitch.  The  general  condition  of  the  animal  should  be 
noted  daily  until  there  is  no  further  danger  from  wound  infec- 


230  SURGICAL  DISEASES 

tion.  Healing  is  usually  completed  in  from  seven  to  twelve 
days.  The  sutures  should  then  be  removed,  and  if  stitch 
abscesses  occur,  the  part  should  be  washed  with  a  disinfectant. 

QUESTIONS 

1.  What  is  the  purpose  of  dehorning  cattle?     Give  different  methods  of 

removing  the  horns. 

2.  Give  the  causes  and  treatment  of  choking. 

3.  What  is  the  purpose  of  castration  and  ovariotomy? 

4.  At  what  age  is  it  best  to  practise  castration  and  ovariotomy? 

5.  In  Avhat  way  should  an  animal  be  prepared  for  castration?     Give  a  de- 

scription of  the  method  of  castration  in  the  different  animals. 

6.  What  special  care  should  be  given  following  castration? 

7.  What  are  some  of  the  complications  that  may  follow  castration? 


PART  V 

PARASITIC  DISEASES 


CHAPTER  XXIV 
PARASITIC  INSECTS  AND  MITES 

Parasitic  insects  are  common  causes  of  skin  diseases  in 
domestic  animals.  The  diseased  conditions  of  the  skin,  and  the 
irritation  that  they  may  cause  the  animal,  depend  on  the  life 
history  and  habits  of  the  parasite.  Species  that  are  unable  to 
live  independently  of  a  host  and  are  permanent  parasites  are 
usually  the  most  injurious  to  the  animal.  This  is  especially 
true  of  parasites  that  are  capable  of  puncturing  the  skin  or 
burrowing  into  it.  Temporary  parasites  may  cause  fatal  forms 
of  disease.  This  is  true  of  the  larvae  of  the  sheep  bot-fly,  which 
develop  in  the  sinuses  of  the  head,  causing  severe  inflammation 
lof  these  parts,  nervous  symptoms  and  death.  The  character 
of  the  symptoms  of  a  parasitic  disease  depends  on  the  habits 
of  the  parasite,  and  the  tissue  or  organ  that  it  may  attack. 

The  parasitic  flies  belong  to  the  order  Dipt  era,  and  the 
families  Muscidce  and  (Estridce.  Fleas  belong  to  the  sub-order 
Pulicidce.  The  order  Herniptera  includes  the  lice,  and  the 
most  important  families  are  PedicuJidce  and  Ricinidce.  Mites 
and  ticks  belong  to  the  order  Acarina.  The'  most  important 
parasites  belonging  to  this  order  are  the  SarcoptidcB  and  I.vodidw. 

CEstridae. — The  three  common  bot-flies  are  the  GastropJiilus 
equi,  Ilijpoderma  lineata  and  (Estriis  oris.  These  flies  are 
important  because  of  the  parasitic  habits  of  their  larvae.  They 
inhabit  the  stomach  and  intestines  of  horses  (Fig.  62)  ;  the 
subcutaneous  tissue  and  skin  of  cattle ;  and  the  sinuses  of  the 
head  and  nasal  cavities  of  sheep. 

The  common  hot-fiy  of  the  horse  {G.  eqid)  has  a  heavy,  hairy 
body.  Its  color  is  bro^^^l,  with  dark  and  yellowish  spots.  The 
female  fly  can  be  seen  during  the  warm  weather,  hovering  around 
the  horse,  and  darting  toward  the  animal  for  the  purpose  of 

233 


234 


PARASITIC  DISEASES 


depositing  the  egg.  The  color  of  the  egg  is  yellow,  and  it 
adheres  firmly  to  the  hair.  It  hatches  in  from  two  to  four 
weeks,  and  the  larva  reaches  the  mouth  through  the  animal  lick- 
ing the  part.  From  the  mouth,  it  passes  to  the  stomach,  where 
it  attaches  itself  to  the  gastric  mucous  membrane  (Fig.  62). 
Here  it  remains  until  fully  developed,  when  it  becomes  detached 
and  is  passed  out  with  the  ftijces.    The  third  stage  is  passed  in  the 


FiQ.  62. — A  piece  of  the  wall  of  the  horse's  stomach  showing  the  bot-fly  larvse  attached. 

ground.  This  takes  place  in  the  spring  and  early  summer 
and  lasts  for  several  weeks,  when  it  finally  emerges  a  mature  fly. 
The  hot-fly  of  the  ox  (11.  lineata)  is  dark  in  color  and  about 
the  size  of  a  honey-bee.  On  warm  days,  the  female  may  be  seen 
depositing  eggs  on  the  body  of  the  animal,  especially  in  the 
region  of  the  heels.  This  seems  to  greatly  annoy  the  animal, 
and  it  is  not  uncommon  for  cattle  to  become  stampeded.     The 


PARASITIC  INSECTS  AND  MITES  235 

egg  reaches  the  mouth  through  the  animal  licking  the  part.  The 
saliva  dissolves  the  shell  of  the  egg  and  the  larva  is  freed.  It 
then  migrates  from  the  gullet,  wanders  about  in  the  tissue  until 
finally  it  may  reach  a  point  beneath  the  skin  of  the  l)ack.  Here 
the  larva  matures  and  forms  the  well-known  swelling  or  warble. 
In  the  spring  of  the  year  it  works  out  through  the  skin.  The 
next  stage  is  spent  in  the  ground.  The  pupa  state  lasts  several 
weeks,  when  the  mature  fly  issues  forth. 

Tlie  hot-fly  of  sheep  (0.  ovis)  resembles  an  overgrown 
house-fly.  Its  general  color  is  brown,  and  it  is  apparently  lazy, 
flying  about  very  little.  This  bot-fly  makes  its  appearance  when 
the  warm  weather  begins,  and  deposits  live  larvae  in  the  nostrils 
of  sheep.  This  act  is  greatly  feared  by  the  animals,  as  shown 
by  their  crowding  together  and  holding  the  head  down.  The 
larva  works  up  the  nasal  cavities  and  reaches  the  sinuses  of  the 
head,  where  it  becomes  attached  to  the  lining  mucous  membrane. 
In  the  spring,  when  fully  developed,  it  passes  out  through  the 
nasal  cavities  and  nostrils,  drops  to  the  gTound,  buries  itself, 
and  in  from  four  to  six  weeks  develops  into  the  mature  fly. 

Symptoms  of  Bot-fly  Diseases. — The  larva?  of  the  bot-fly 
of  the  horse  do  not  cause  characteristic  symptoms  of  disease. 
Work  horses  that  are  groomed  daily  are  not  hosts  for  a  large 
number  of  "  bots,"  but  young  and  old  horses  that  are  kept  in  a 
pasture  or  lot  and  seldom  groomed  may  become  unthrifty  and 
"  pot  bellied,"  or  show  symptoms  of  indigestion. 

Cattle  suffer  much  pain  from  the  development  of  the  larvae 
of  the  II.  llneata.  During  the  spring  of  the  year,  the  pain  re- 
sulting from  the  presence  of  the  larva?  beneath  the  skin  and  the 
penetration  of  the  skin  is  manifested  by  excitement  and  running 
about.  Besides  the  loss  in  milk  and  beef  production,  there  is  a 
heavy  yearly  loss  from  the  damage  to  hides. 

The  parasitic  life  of  the  bot-fly  of  sheep  results  in  a  severe 
catarrhal  inflammation  of  the  mucous  membrane  lining  the 
sinuses  of  the  head,  and  a  discharge  of  a  heavy,  pus-like  material 


236  PARASITIC  DISEASES 

from  the  nostrils.  The  irritation  produced  by  the  larvse  may  be 
so  serious  at  times  as  to  result  in  nervous  symptoms  and  death. 

Treatment  of  Bot-fly  Diseases. — The  treatment  of  the  differ- 
ent bot-fly  diseases  is  largely  preventive.  This  consists  in  either 
the  destruction  of  the  eggs  or  the  larvae 

The  different  methods  of  destroying  the  eggs  of  the  bot-fly 
of  the  horse  are  clipping  the  hair  from  the  part,  scraping  off 
the  eggs  with  a  sharp  knife,  or  destroying  them  by  washing  the 
part  infested  with  eggs  with  a  two  or  three  per  cent  water  solu- 
tion of  carbolic  acid.  This  should  be  practised  every  two  weeks 
during  the  period  when  the  female  deposits  the  eggs. 

Housing  the  cattle,  or  applying  water  solutions  of  certain 
preparations  to  the  skin  that  may  keep  the  female  from  deposit- 
ing eggs,  may  be  practised  for  the  prevention  of  the  ox-warble. 
The  most  practical  method  of  ridding  cattle  of  this  pest  is  to 
destroy  the  larvic.  This  can  be  done  by  examining  each  animal 
and  locating  the  swelling  or  warble  and  injecting  a  few  drops 
of  kerosene  into  the  opening  in  the  skin.  A  better  method  is  to 
enlarge  the  opening  in  the  skin  with  a  sharp  knife,  squeeze  out 
the  grub  and  destroy  it.  This  should  be  practised  in  late  winter 
and  early  spring. 

The  application  of  pine  tar  to  the  nostrils  of  sheep  is  the 
most  practical  method  of  preventing  "  grub  in  the  head."  This 
should  be  practised  every  few  days  during  the  summer  months. 
A  very  good  preventive  measure  is  plenty  of  shade  for  the  flock. 
Valuable  animals  may  be  treated  by  trephining  into  the  head 
sinus  and  removing  the  "  grub." 

Lice. — The  sucking  lice  belong  to  the  genus  Ilcematopinus, 
and  the  biting  lice  of  mammals  belong  to  the  genus  Trichodectes. 
Different  species  of  sucking  and  biting  lice  occur  on  the  different 
species  of  farm  animals.  Poultry  act  as  hosts  for  many  differ 
ent  species  of  biting  lice  belonging  to  the  following  genuses: 
Lipiurus,  Goniodes,  Goniocotes  and  Menopon. 

The  common  sucking  lice  occurring  on  animals  are  the  large- 


PARASITIC  INSECTS  AND  MITES 


237 


headed  horse  louse,  //.  macrocephalus;  the  long-nosed  ox  louse, 
//.  tenuirostris;  the  larg-e-bellied  ox  louse,  H.  eurysternus;  the 
H.  stenopses  of  sheep ;  //.  suis  of  swine ;  and  the  //.  piliferus  of 
the  dog. 

The  common  hiting  lice  (Fig.  63)  that  are  found  on  domestic 
animals  are  the  T.  pilosus  and  T.  puhescens  of  solipeds,  T. 
scalaris  of  the  ox,  T.  spcerocephalus  of  sheep  and  goats,  T.  laius 
and  T.  suhrostratus  of  the  dog  and  cat.  Menopon  palidum, 
L'lpiurus  rariahllis  and  Gon- 
oides  dissimilis  are  the  com- 
mon lice  found  on  poultry. 

Symptoms  of  Lice. — The 
s^Tnptoms  of  lousiness  depend  ^ 
on  the  variety  of  lice  present, 
the  degree  to  which  the  ani- 
mal is  infested  with  them,  its 
physical  condition  and  tlie 
care  that  it  receives.  Lice 
multiply  more  rapidly  and 
cause  greater  loss  during  the 
winter  months  than  they  do 
in  the  summer,  when  the 
animals  are  not  housed  and 
the  opportunity  for  infection 
from  the  surroundings  is  not 
so  great.  The  sucking  louse  (Fig.  G4)  is  the  most  injurious 
and  irritating.  The  irritation  and  loss  of  blood  that  the  animal 
may  suffer  when  badly  infested  by  this  parasite  may  result 
in  marked  unthriftiness.  Young  and  old  animals  that  are  not 
well  cared  for  suffer  most.  The  biting  louse  may  bite  through 
the  superficial  layer  of  the  skin,  and  cause  the  animal  to  bite 
and  rub  the  part.  This  irritation  to  tlie  skin  prevents  the 
animal  from  becoming  rested,  and  after  a  time  seriously  inter- 
feres with  its  thriftiness. 


Fig.  63. — Biting  louse. 


238 


PARASITIC  DISEASES 


Horses  and  mules  show  a  staring,  dirty,  rough  coat.  The 
mane  and  tail  may  become  broken  and  matted.  The  animal 
nibs  against  the  stall,  fences  and  trees,  and  bites  the  skin  in  its 
efforts  to  relieve  the  irritation.  On  examining  the  coat,  nits  are 
fonnd  adhering  to  the  hair  (Fig.  G5).  We  should  examine  the 
parts  of  the  skin  covered  by  the  long  hair  for  the  sucking  lice ; 
and  the  withers,  abdomen  and  limbs  for  the  biting  lice. 


, ^ 

I 


FiQ.   64. — Sucking  louse  (much  enlarged). 


Fio.   G.5. 


-Nits  attached  to  hair  (much 
enlarged). 


The  symptoms  of  lousiness  in  cattle  are  about  the  same  as 
occur  in  horses.  Licking  and  rubbing  the  skin  are  prominent 
symptoms  in  cattle,  and  the  coat  becomes  dirty  and  rough.  The 
licked  part  is  matted  and  curled.  The  lice  may  be  discovered 
by  parting  the  hair  along  the  back  and  rump. 

The  biting  louse  of  sheep  causes  the  fleece  to  become  matted 
and  tufts  of  wool  are  pulled  out.  This  is  brought  about  by  the 
sheep  rubbing  and  nibbling  the  fleece,   and  the  lice  cutting 


PARASITIC  INSECTS  AND  MITES  239 

through  the  wool.     The  loss  due  to  the  damage  to  the  fleece  is 
usually  greater  than  that  resulting  from  unthriftiness. 

The  hog-louse  is  the  largest  specie  known.  As  well  as  the 
largest,  it  is  the  most  common  of  all  lice  found  on  domestic  ani- 
mals. The  favorite  points  of  attack  are  the  under  surface  of 
the  body,  the  neck  and  the  inside  of  the  thighs.  The  irritation 
and  itching  are  severe,  and  the  hog  rubs  and  scratches  the  skin. 
Young  hogs  suffer  most  from  this  parasite,  and  their  thriftiness 
is  greatly  interfered  with. 

The  long-haired  breeds  of  dogs  suffer  more  from  lice  than 
the  short-haired  breeds.  The  almost  constant  scratching  and 
biting  of  the  skin  result  in  its  becoming  badly  irritated  and 
scabby.  The  symptoms  differ  little  from  irritation  to  the  skin 
caused  by  fleas,  but  the  presence  of  biting  or  sucking  lice  en- 
ables the  person  making  the  examination  to  determine  the  cause 
of  the  irritation. 

Lice  are  the  most  common  parasites  of  poultry.  It  is  un- 
common to  meet  with  a  flock  of  fowls  that  are  not  hosts  for  one 
or  more  of  the  many  different  varieties  of  bird  lice.  Restless- 
ness, picking,  scratching,  flapping  the  wings,  abandoning  the 
nest  and  loss  of  condition  are  common  symptoms.  Young  birds 
suffer  most  from  lice.  This  is  especially  true  of  young  chickens, 
death  frequently  resulting.  Old  fowls  may  show  little  incon- 
venience unless  badly  infested.  The  finding  of  the  lice  with  the 
head  imbedded  in  the  skin  or  on  the  feathers  enables  the  person 
making  the  examination  to  positively  diag-nose  the  case.  The 
head,  back,  region  of  the  vent  and  beneath  the  wings  are  the 
parts  that  should  be  carefully  examined  for  lice. 

Treatment  of  Lousiness. — The  preventive  treatment  is  very 
important.  This  consists  in  carefully  examining  all  animals 
or  birds  that  have  been  purchased  recently,  and  if  found  to 
harbor  lice,  excluding  them  from  the  herd  or  flock  until  after 
they  have  been  properly  treated. 

It  is  impossible  to  rid  animals  of  lice  if  the  quarters  are  not 


240  PARASITIC  DISEASES 

thoroughly  cleaned  and  disinfected.  This  is  necessary  in  order 
to  destroy  lice  that  have  become  scattersd  about  by  the  lousy 
animals,  and  prevent  the  reinfection  of  the  treated  animals. 
The  best  method  to  use  in  cleaning  the  quarters  is  to  remove  all 
litter  and  manure  from  the  stable  or  houses  and  their  immediate 
surroundings.  It  should  be  burned,  or  hauled  to  a  field  or  lot 
where  other  animals  cannot  come  in  contact  with  it  for  a  few 
months.  The  walls,  floors  and  partitions  should  be  sprayed 
with  a  three  per  cent  water  solution  of  liquor  cresolis  compositus. 
Lime  may  be  scattered  about  the  buildings,  yards  and  runs. 
The  most  satisfactory  method  of  destroying  lice  on  the  bodies 
of  animals  is  by  washing  or  dipping  in  a  water  solution  or 
mixture  of  some  reliable  disinfectant  or  oil. 

Running  hogs  through  a  dipping  tanh  that  contains  a  one 
or  two  per  cent  water  solution  of  liquor  cresolis  compositus,  or  a 
coal  tar  disinfectant,  or  that  has  from  three-fourths  to  one  and 
one-half  inches  of  oil  on  top  of  the  water,  is  the  most  satisfactory 
method  of  destroying  the  hog  louse.  Because  of  the  thinness  of 
the  hog's  coat  and  the  danger  from  irritating  the  skin  when 
strong  solutions  of  a  disinfectant  are  used,  most  swine  breeders 
prefer  crude  oil  as  a  remedy  for  lousiness  in  hogs.  Crude  oil 
may  be  applied  to  the  bodies  of  hogs  with  a  swab.  If  this  method 
is  practised  instead  of  dipping,  it  is  advisable  to  crowd  the 
hogs  into  a  small  pen,  and  apply  the  oil  in  front  and  between 
the  thighs  and  back  of  the  arms.  This  may  be  practised  during 
the  cold  weather  when  it  is  impossible  to  dip  the  animals. 

Horses  may  be  )vashed  with  a  one  or  two  per  cent  water 
solution  of  liquor  cresolis  compositus,  or  a  coal  tar  disinfectant. 
If  the  weather  is  cold,  it  is  advisable  to  pick  a  sunny  day,  and 
blanket  tlie  animal  after  rubbing  it  as  dry  as  possible  in  order  to 
prevent  chilling  and  catching  cold. 

Cattle  may  be  treated  in  the  same  manner  as  horses.  Mercu- 
rial ointment  rubbed  in  small, amounts  on  the  skin  back  of  the 
horns  and  ears,  where  the  animal  cannot  lick  it,  is  a  common 


PARASITIC  INSECTS  AND  MITES 


241 


remedy.     The  absorption  of  a  small  amount  of  this  drug  does  the 
animal  no  harm,  hut  a  larger  quantity  may  salivate  it. 

Sheep  are  treated  hy  dipping  in  a  water  solution  of  a  reliahlc 
coal  tar  disinfectant.  This  should  not  he  practised  during  cold 
weather,  as  the  fleece  does  not  dry  out.  Insect  powder  may  he 
dusted  into  the  fleece  when  it  is  impossible  to  dip  the  animal. 

A  very  satisfactory  treatment  for  lousiness  in  dogs  and  cats 
is  to  wash  them  with  earholized  soap.  We  should  wait  a  few 
minutes  before  rinsing  oft"  the  soapy  lather  and  drying  the  coat. 

A  number  of  different  remedies  are  used  for  the  treatment 
of  lousiness  in  poultry.  Dust 
baths  and  insect  powder  are 
recommended.  Ointments  are 
commonly  used.  One  part  sul- 
fur and  four  parts  vaseline,  or 
lard,  may  be  made  into  an  oint- 
ment and  applied  to  the  head, 
neck,  under  the  wings  and 
around  the  vent.  ^lercurial 
ointment  may  be  applied  to  the 
margin  of  the  vent.  Xeither 
of  them  should  he  used  for  de- 
stroying lice  on  young  chicks.  Mercurial  ointment  should  be 
used  very  carefully  because  of  its  poisonous  eft'ect.  Lard  may 
be  used  for  destroying  lice  on  young  chicks.  Crude  petroleum 
may  be  sprayed  among  the  feathers  by  a  hand-sprayer,  while 
the  fowls  are  suspended  by  the  feet. 

Xone  of  the  disinfectants  and  oils  recommended  for  dipping 
and  washing  lousy  animals  destroy  the  nits.  This  makes  it 
necessary  to  re-treat  the  animal  in  from  eight  to  ten  days  after 
the  first  treatment. 

The  Sheep-tick. — This  is  not  a  true  tick.    It  resembles  a  fiy 
more  than  it  does  a  tick,  and  its  right  name  is  Melophagus 
ovinus  (Fig.  66).     Louse-fly  is  a  better  name  for  this  parasite 
16 


Fig.   C6. — Sheep-tick. 


242 


PARASITIC  DISEASES 


than  tick,  as  its  entire  life  is  spent  on  the  body  of  a  sheep.  The 
general  color  of  the  body  is  brown.  The  legs  are  stout,  covered 
with  hair  and  armed  with  hooks  at  their  extremities.  The  mouth 
parts  consist  of  a  tubular,  toothed  proboscis  with  which  the  para- 
site punctures  the  skin  and  sucks  the  blood.  Within  a  few  hours 
after  birth,  the  larvae  develop  into  pupip,  which  are  hard,  dark 
bro'wn  in  color  and  firmly  glued  to  the  wool.  The  young  louse- 
fly  emerges  from  the  pupa  in 
from  three  to  four  weeks. 

The  sheep-tick  is  a  very 
common  external  parasite. 
The  adult  parasites  and  the 
pupaj  are  large  and  easily 
found.  When  badly  infested 
with  ticks,  a  sheep  will  rub, 
dig  and  scratch  the  skin  and 
fleece.  This  results  in  pieces 
of  wool  becoming  pulled  out 
and  the  fleece  appears  ragged. 
After  clipping  the  ticks  mi- 
grate from  the  ewes  to  the 
lambs,  which  may  become  un- 
thrifty and  weak. 

The  treatment  consists  iti 
dipping  the  flock  in  a  one  or 
two  per  cent  water  solution  of  a  coal-tar  dip.  Dips  containing 
arsenic  are  most  effective  in  ridding  sheep  of  ticks. 

Scabies. — This  parasitic  disease  is  one  of  the  oldest  and 
most  prevalent  diseases  of  the  skin.  It  is  commonly  known  as 
scab  or  mange.  The  animals  most  commonly  affected  are  sheep, 
horses  and  cattle. 

The  disease  is  caused  by  small  mites  or  acari  that  are  natu- 
rally divided  into  the  t<arcoptes,  which  burrow  under  the  epi- 
dermis, forming  galleries ;  the  Psoroptes,  which  live  on  the  sup 


Fig.  67. — Sheep  scab  mite,  ventral  view. 
(From  Farmers'  Bulletin  No.  159,  United 
States  Department  of  Agriculture.) 


PARASITIC  INSECTS  AND  MITES  243 

face  of  the  skin  where  they  are  sheltered  by  scabs  and  scurf;  and 
the  Symbioies,  which  also  live  on  the  surface  of  the  skin,  but 
prefer  the  regions  of  the  hind  feet  and  legs. 

Acari  multiply  rapidly  and  live  their  entire  life  on  the  body 
of  the  host.  A  new  generation  is  produced  in  about  fifteen  days. 
Gerlach  has  estimated  the  natural  increase  in  three  months  at 
1,000,000  females  and  500,000  males.  Scab  and  mange  are 
exceedingly  contagious  diseases. 


Fig.   6S. — riheep  scab. 

Common  sheep  scab  is  caused  by  that  specie  of  mites  known 
as  the  Psoroptes  communis  var.  oris  (Fig.  67).  Any  part  of  the 
body  may  become  affected.  The  bites  of  the  mites  greatly 
irritate  the  skin,  and  the  animal  scratches,  bites  and  rubs  the  part 
in  its  effort  to  relieve  the  intense  itching.  The  skin  becomes  in- 
flamed and  scabby,  the  wool  is  pulled  and  rubbed  out,  and  the 
fleece  becomes  ragged  (Fig,  68).  By  pulling  wool  out  of  the 
newly  infested  area,  or  collecting  skin  scrapings  and  placing 
this  material  on  black  paper  in  a  sunny,  warm  place,  the  mites 


2ti  PARASITIC  DISEASES 

may  be  seen  crawling  over  the  paper.  This  method  of  diagnosis 
should  be  resorted  to  in  all  suspicious  cases  of  skin  disease,  and 
before  the  disease  has  developed  to  any  great  extent. 

The  mite  that  most  commonly  causes  mange  in  cattle  is  the 
Psoroptes  commiuiis  var.  hovis.  It  may  invade  the  skin  in  the 
ditt'erent  regions  of  the  body,  but  it  is  in  the  regions  of  the  tail 
and  thighs  that  the  first  evidence  of  the  mange  is  noticed.  The 
animal  rubs,  scratches,  and  licks  the  part.  The  itching  is  intense. 
The  hair  over  the  part  is  lost  and  the  skin  appears  inflamed, 
thickened,  moist,  or  covered  with  white  crusts.  Cracks  and  sores 
may  form  in  the  skin.  The  examination  of  scrapings  from  the 
inflamed  skin  should  be  practised  in  order  to  confirm  the 
diagnosis. 

Mange  in  horses  may  be  caused  by  either  psoroptic  or 
sarcoptic  mites.  Psoroptes  communis  var.  equi  seems  to  be  the 
more  common  parasite.  The  itching  is  intense.  The  inflamed 
areas  are  small  at  first  and  scattered  over  the  regions  of  the 
rump,  back  and  neck  (Fig.  G9).  After  a  time  the  small  areas 
come  together  and  form  large  patches,  and  further  spreading  of 
the  inflammation  results  from  grooming,  scratching  and  biting 
the  skin.  Scattered,  elevated  eruptions  on  the  skin  from  which 
the  hair  has  dropped  out  are  first  noticed.  These  parts  may 
show  yellowish  scabs.  Later  the  skin  is  thickened,  smooth, 
wriifliled,  cracked,  or  covered  with  sores.  Scrapings  made  from 
the  inflamed  areas  of  the  skin  may  show  the  psoroptic  mites. 

Mange  in  Jiogs  is  comparatively  rare.  It  is  caused  by  one  of 
the  sarcoptic  mites.  The  thin  portions  of  the  skin  are  usually 
first  invaded.  There  are  violent  itching  and  rubbing,  and  small, 
red  elevations  occur  on  the  skin  in  the  region  of  the  ears,  eyelids 
or  inner  surface  of  tlie  thighs,  depending  on  the  part  first  in- 
vaded. The  skin  becomes  greatly  thickened  and  covered  with 
crusts  and  scabs.    Pus  formation  and  ulceration  may  occur. 

Treatment  of  Scab  and  Mange. — A  careful  inspection  of 
recently  purchased  animals  that  pass  through  stockyards,  or  are 
shipped  from  sections  where  scab  and  mange  are  common  skin 


PARASITIC  INSECTS  AND  MITES  245 

diseases,  is  an  important  preventive  measure.  Infected  animals 
should  be  completely  isolated  from  the  herd,  and  kept  apart  from 
other  animals  until  after  they  have  been  treated.  Hogs  that  are 
slightly  infected  should  be  quarantined  and  treated.  If  badly 
affected,  they  should  be  killed,  and  the  carcass  disposed  of  by 
burning  or  burvina'. 


Fig.  69. — A  severe  case  of  mange. 


Tlic  different  remedies  used  in  the  treatment  of  the  disease 
may  be  applied  by  dipping,  hand  dressing  or  washing,  pouring, 
smearing  and  spotting.  The  first  method  is  the  most  satisfactory. 
The  last  method  may  be  used  when  a  small  area  of  the  skin  is 
involved,  and  during  the  cold  weather.  Washing  or  dipping 
the  animal  with  a  two  per  cent  water  solution  of  liquor  cresolis 
compositus  is  an  effective  remedy  for  the  psoroptic  forms  of 


246  PARASITIC  DISEASES 

scab  and  mange.  Tobacco,  lime  and  sulfur,  and  arsenical  dips 
are  recommended  in  the  treatment  of  sheep  and  cattle.  Oint- 
ments are  recommended  for  animals  that  are  slightly  affected 
with  mange.  Lime  and  sulfur  dips  are  recommended  by  the 
Bureau  of  Animal  Industry.  Small  infected  areas  of  the  skin 
may  be  treated  by  applying  sulfur-iodide  ointment.  The  fol- 
lowing ointment  is  commonly  recommended:  potassium  sulfide 
ten  parts,  potassium  carbonate  two  parts,  and  lard  three  hun- 
dred parts. 

Sheep  cannot  be  safely  dipped  for  scab  during  the  cold 
weather.  If  thickened  and  scabby,  the  skin  should  be  scrubbed 
with  the  dip,  or  the  animal  prepared  for  dipping  or  washing  by 
first  clipping  the  hair  or  wool  and  scrubbing  the  skin  with  water 
and  a  good  soap.  In  order  to  prevent  reinfection,  it  is  necessary 
to  remove  the  animal  to  new  quarters,  or  thoroughly  clean  and 
disinfect  the  old.  It  is  necessay  to  wash  or  spray  the  fences, 
floors,  walls,  brushes  and  curry-combs  with  a  disinfecting  solu- 
tion. Manure  and  other  litter  should  be  removed  to  a  place 
where  there  is  no  danger  from  its  distributing  the  infection. 

Diseases  of  Poultry  Caused  by  Mites. — Mites  or  acarina 
that  cause  diseases  of  poultry  may  live  on  the  feathers,  beneath 
the  skin,  and  within  the  body  of  the  fowl. 

The  small,  red  mite  {Dermanyssus  gallinw)  remains  on  the 
surface  of  the  body  only  when  feeding,  and  spends  the  rest  of  the 
time  under  collections  of  filth  and  in  cracks  in  the  roosts  and 
walls  of  the  house.  This  parasite  causes  the  birds  to  become 
restless,  emaciated  and  droopy. 

A  very  small  mite  (Sarcoptes  mutans)  is  the  cause  of  scaly 
leg.  It  lives  under  the  skin.  The  joints  of  the  feet  appear 
affected,  and  the  foot  and  leg  become  enlarged,  roughened  and 
scaly. 

Depluming  scabies  is  caused  by  Sarcoptes  Uvvis  var.  gallinw. 
This  mite  causes  the  feathers  to  break  off  at  the  surface  of  the 
skin.     Masses  of  epidermic  scales  may  form  around  the  broken 


PARASITIC  INSECTS  AND  MITES  247 

ends   of  the   feathers.      The   diagnosis   can   be   confirmed  by 
examining  the  skin  lesions  and  finding  the  mite. 

The  air  sac  mite  {Cytodites  nudus)  may  cause  sufficient 
irritation  to  the  mucous  membrane  lining  the  air  sacs  to  seri- 
ously obstruct  the  air  passages  with  mucus,  or  produce  death 
from  exhaustion.  A  post-mortem  examination  of  a  fowl  that 
has  died  of  this  disease  shows  the  mites  on  the  surface  of  the 
lining  membrane  of  the  air-sacs.  They  appear  as  a  white  or 
yellow  dust. 

Treatment  of  Poultry  Diseases  Caused  by  Mites. — Diseases 
of  poultry  caused  by  mites  may  be  prevented  by  quarantining  all 
recently  purchased  birds  for  a  period  of  from  two  to  four  weeks, 
and  by  keeping  the  poultry  houses  clean.  Birds  that  are  found 
infested  with  parasites  should  be  destroyed  or  returned.  In 
case  the  bird  is  valuable  and  suffering  from  external  parasites 
only,  it  should  be  given  the  necessary  treatment. 

Red  mites  may  he  destroyed  by  thoroughly  cleaning  the  poul- 
try house,  and  spraying  the  roosts,  nests,  walls  and  floor  with  a 
three  per  cent  water  solution  of  liquor  cresolis  compositus.  This 
should  be  repeated  twice  a  week  for  two  weeks. 

Scaly-leg  may  be  treated  by  applying  a  penetrating  oil  to  the 
feet  and  lower  part  of  the  leg.  It  is  advisable  to  first  remove 
the  scales  by  scrubbing  the  part  with  soap  and  warm  water. 
Dipping  the  feet  in  a  mixture  of  kerosene  one  part  and  linseed 
oil  two  parts  is  recommended.  This  should  be  repeated  as  often 
as  necessary. 

QUESTIONS 

1.  Describe  the  different  bot-flies. 

2.  Give  the  life  history  of  the  bot-fly  of  the  horse;  of  tlie  ox;  of  sheep. 

3.  Give  the  symptoms  of  bot-fly  diseases. 

4.  Give  the  symptoms  of  lousiness. 

5.  Give  treatment  for  lousiness  of  different  farm  animals. 

6.  What  is  the  damage  from  the  sheep-tick?     Give  treatment. 

7.  Describe  the  injury  from  scabies  and  mange. 

8.  Give  treatments  for  these  diseases. 

9.  Mention  the  several  poultry  mites  and  tell  how  to  treat  them. 


CHAPTER  XXV 


ANIMAL  PARASITES 

The  common  parasitic  diseases  of  domestic  animals  are 
caused  by  the  followin<>'  groups  of  worms :  Flukes  or  trema-  . 
toides;  tapeworms  or  Cestoides;  thorn-headed  worms  or  Acantho- 
cephalesj  and  round-worms  or  Nematoids.  Flat  worms,  such  as 
tapeworms  and  flukes,  re(|,uire  secondary  hosts.  The  immature 
and  mature  forms  of  tapeworms  are  parasites  of  vertebrate 
animals,  but  an  invertebrate  host  is  necessary  for  the  completion 

of  tlie  life  cycle  of  the 
fluke."  The  hog  is  the 
only  specie  of  domestic 
animals  that  becomes 
a  host  for  the  thorn- 
headed  worm.  The 
round-worm  is  a  very 
common  parasite. 
There  are  many  spe- 
cies belonging  to  this 
class. 

Distoma  Hepati- 
cum  (Common  Liver 
Fluke). — Sheep  are  the  most  common  hosts  for  this  parasite.  It 
is  present  in  the  gall  ducts  and  livers,  and  causes  a  disease  of  the 
liver  known  as  liver  rot.  The  liver  fluke  is  flat  or  leaf -like  and 
from  thirteen  to  fifteen  mm.  long  (Fig.  TO).  The  head  portion  is 
conical.  It  has  an  oval  and  ventral  sucker,  and  the  body  is  cov- 
ered with  scaly  spines.  The  eggs  are  oval  and  brownish  in  color. 
The  life  history,  in  brief,  is  as  follows:  Each  adult  is  capa- 
ble of  producing  an  immense  numl)cr  of  eggs  which  are  carried 
down  the  bile  ducts  with  the  bile  to  the  intestine,  and  are  passed 
off  with  the  faeces.  Under  favorable  conditions  for  incubation, 
248 


FiQ.   70.— Liver  flukes. 


ANIMAL  PARASITES  249 

such  as  warm,  moist  surroundings,  the  ova  or  eggs  hatch  and  the 
ciliated  embryos  become  freed.  The  embryo  next  penetrates 
into  the  body  of  certain  snails  and  encysts.  The  sporocyst,  as  it 
is  now  called,  develops  into  a  third  generation  known  as  redia 
which  escape  from  the  cyst.  The  daughter  redia  or  cercaria, 
as  they  are  now  termed,  leave  the  body  of  the  snail  and  finally 
become  encysted  on  the  stems  of  grass,  cresses  and  weeds.  When 
taken  into  the  digestive  tract  of  the  animal  grazing  over  in- 
fested ground,  the  immature  flukes  are  freed  by  the  digestive 
juices.  They  then  pass  from  the  intestine  into  the  bile  ducts. 
The  period  of  development  varies  from  ten  to  twenty  weeks; 
each  sporocyst  may  give  rise  to  from  five  to  eight  redia  and  each 
redia  to  from  twelve  to  twenty  cercaria. 

Fluke  diseases  occur  among  animals  pastured  on  low,  wet, 
undrained  land.  Drying  ponds  and  lakes  are  the  homes  of  the 
fresh  water  snails,  and  in  such  places  there  are  plenty  of  hosts 
for  the  immature  flukes.  Wet  seasons  favor  the  development  of 
this  parasite.  Cattle  and  sheep  that  pasture  on  river  bottom 
land  in  certain  sections  of  the  southern  portion  of  the  United 
States  are  frequently  affected  with  fluke  diseases. 

The  symptoms  of  liver  rot  of  sheep  may  be  divided  into  two 
stages.  The  first  stage  is  marked  by  increase  in  weight  and 
improved  condition.  In  the  second  stage  of  the  disease,  the 
animal  shows  a  pale  skin  and  mucous  membrane,  dropsical 
swellings,  loss  of  flesh  and  weakness.  The  character  of  the 
symptoms  of  the  disease  depends  on  the  age  of  the  animals  and 
the  care  that  they  receive.  Young,  poorly  cared  for  animals 
suffer  severely  from  the  'disease,  and  the  death  rate  is  usually 
heavy.  The  finding  of  fluke  ova  in  the  ficces  is  conclusive  evi- 
dence of  the  nature  of  the  disease.  It  may  be  advisable  to  kill 
one  of  the  sick  animals,  and  determine  the  nature  of  the  disease 
by  a  post-mortem  examination. 

The  treatment  is  preventive.  Drainage  water  from  a  pasture 
infested  with  snails  harboring  immature  flukes  is  a  source  of 


250 


PARASITIC  DISEASES 


FlQ. 

71. 


Fio. 


Fig.  71. — Tapeworm  larvae  in  liver  {Echinococcus  polymorphus). 
Fig.  72. — Tapeworms. 

infection,  and  should  not  be  used  as  a  water  supply  for  cattle 
and  sheep.  In  sections  where  the  disease  is  prevalent,  sheep 
should  not  be  pastured  on  low,  poorly-drained  land.     Such  land 


ANIMAL  PARASITES  251 

should  be  used  for  pasturing  horses  and  cattle,  but  if  possible, 
it  should  be  first  drained  and  cultivated.  Careful  feeding  and 
good  care  may  help  the  affected  animals  to  recover. 

Tapeworms  or  Cestoides. — Taj^eworms  are  formed  by  a 
chain  of  segments,  joined  together  at  their  ends,  and  are  flat  or 
ribbon-shaped  (Fig.  Tl).  The  head  segment  is  small,  and 
possesses  either  hooks  or  suckers.  It  is  by  these  that  the  worm 
attaches  itself  to  the  lining  membrane  of  the  intestine.     The 


Fig.  73. — Tapeworm  larvse  in  thu  ijentuueum  {Cysticercus  cellulosa) , 

anterior  segments  are  smaller  and  less  mature  than  the  posterior 
segments.  Each  segment  is  sexually  complete,  possessing  both 
the  male  and  female  organs,  and  when  mature,  one  or  more  of 
them  break  off  and  are  passed  out  with  the  fa?ces.  The  mature  or 
ripe  segments  are  filled  with  ova.  On  reaching  the  digestive 
tract  of  a  proper  host,  usually  with  the  drinlving  water  or  fodder, 
the  embryo  is  freed  from  the  egg.  The  armed  emhryo  uses  its 
booklets  in  boring  its  way  through  the  wall  of  the  intestine.  It 
then  wanders  through  the  tissues  of  its  host  until  it  finally 
reaches  a  suitable  place  for  development  (Figs.  71  and  73),    On 


252  PARASITIC  DISEASES 

coming  to  rest,  it  develops  into  the  larva  or  bladder- worm,  which 
when  eaten  by  a  proper  host  gives  rise  to  the  matnre  tapeworm. 
The  following  tables  give  the  most  important  tapeworms : 
Adult  Forms 

Name                                                                              Host  Organ 

Taenia    expansa     Sheep  and  ox  Intestine 

Tajnia  finibriata    Sheep  Liver 

Ta>nia    denticulata    Cattle  Intestine 

Taenia  alba   Cattle  Intestine 

Taenia  perfoliata   Solipeds  ■  Intestine 

Ta»nai  mamillana    Solipeds  Intestine 

Taenia  echinococcus Dog  intestine 

Larval  Forms 

Name  Host 

Cysticercus  bovis    Cattle 

Cysticercus  cellulosa    Swine   and   man 

Cysticercus  tennicoUis  Cattle,  sheep  and  swine 

Coenurus   cerebralis    Cattle   and   sheep 

Echinococcus  polymorphus   C  attle,  sheep,  swine  and  man 

The  adnlt  tapeworms  Tamice  saghiata  and  solemn,  of  which 
the  Cysticerci  bovis  and  cellulosa  are  the  larva?  forms,  occur  in 
man.  The  larva*  are  present  in  meat  and  pork,  and  this  form  of 
parasitism  is  termed  beef  measles  in  cattle  and  pork  measles  in 
hogs.  Man  becomes  host  for  these  two  forms  of  tapeworms 
through  eating  measly  pork  or  beef  that  is  not  properly  cooked. 

The  dog  is  the  host  for  Tcenice  marginaia,  coenurus  and 
echinococcus.  The  larva*  forms  of  these  toeniw  are  the  Cysti- 
cercus tennicoUis,  Coenurus  cerehralis  and  Echinococcus  poly- 
morphus. C.  tennicoUis  is  a  parasite  of  the  serous  or  lining  mem- 
branes of  the  body  cavities.  It  is  not  of  great  economic  importance. 
C.  cerehralis  is  a  parasite  of  the  brain  of  sheep,  and  may  cause  a 
heavy  death  rate  in  flocks  that  are  infested  with  it.  E.  polymor- 
phus is  a  parasite  of  the  liver,  but  it  may  occur  in  other  organs. 

The  Thorn-headed  Worm  or  Acanthocephale, — This  para- 
sit©  requires  a  secondary  host.  In  this  case  a  particular  species 
of  the  May-beetle  larva  or  white  grub  that  is  commonly  found 
about  manure  piles  and  in  clover  pastures  is  the  host.  The 
hog  eats  a  white  grub  that  is  host  for  the  larval  form.     The 


ANIMAL  PARASITES  253 

digestive  juices  free  the  larva,  it  then  becomes  attached  to  the 
intestinal  mucous  membrane  and  develops  into  the  adult  thorn- 
headed  worm  (Fig.  74).  This  parasite  is  characterized  by  a 
hooked  proboscis  or  thorn  at  its  anterior  extremity,  and  the 
absence  of  a  distinct  digestive  tract.  The  male  is  much  smaller 
than  the  female.  The  eggs  are  passed  out  of  the  intestine  with 
the  ftpces. 


Fig.  74. — Thorn-headed  worms. 

The  Round-worms  or  Nematoids, — Eound-worms  are  very 
common  parasites  of  domestic  animals  (Fig.  75).  This  group 
of  worms  is  characterized  by  their  cylindrical  form,  the  presence 
of  a  true  digestive  canal  and  the  separation  into  two  sexes,  male 
and  female.  The  life  history  is  more  simple  than  in  the  flat 
wonns.  Intermediate  hosts  are  not  required  for  the  develop- 
ment of  the  common  forms.  The  eggs  and  embryos  are  deposited 
by  the  female  in  the  intestinal  tract,  air  passages,  or  excretory 
ducts  of  the  kidneys  of  the  host.  Development  may  be  com- 
pleted here,  or  the  eo-gs  and  embryos  are  passed  oif  with  the  body 
excretions.     They  may  live  for  a  short  time  outside  the  animal 


254 


PARASITIC  DISEASES 


body,  or  undergo  certain  development  and  again  infest  a  host  of 
the  same  species  from  which  they  came,  through  the  water,  grass 
and  fodder  that  the  animal  may  take  into  its  digestive  tract. 


Fig.   75. — -Large  round-worm  in  intestine  of  hog. 

The  following  species  of  nematoids  are  common  parasites 
of  domestic  animals : 

SOLIPEDS 
Species  Organ 

Ascaris  megalocephala     Intestines 

Sclerostoma  equinum Large  intestine  and  blood-vessels 

Sclerostoma  tetracanthum    Large  intestine 

Oxyrus  curvula Large  intestine 

Oxyrus  mastigodes  Large  intestine 

Cattle 

Species  Organ 

Strongj'lus  convolutus  Abomasiim 

Ascaris   vituli    Small  intestine  (calves) 

Strongj'lus  ventricosus    Small  intestine 

CEsophagostomum  inflatum    Large  intestine 

Trichoccphalus    afllns    Large  intestine 

Strongylus  micrurus   Bronchi 

Strongylus  puhnonaris   Bronchi 


ANIMAL  PARASITES  255 

I  Sheep 

Species  Organ 

Haemoncluis  contortiis   Al)omasum 

Ascaris  ovis   Small  intestine 

Strongylus  filicollis    Small  intestine 

CEsopliagostomuni  colunibianum Intestines 

Uncinaria  cernua    Small    intestine 

Trichocephalus  aflins    Large  intestine 

Strongylus  filar ia Eronclii 

Strongylus  rufescens   Bronchi  and  air  follicles 

Swine 

Species  Organ 

Ascaris  suis   Intestines 

(Esophagostomum  dentatum     Large  intestine 

Trichocephalus  crenatus    Large  intestine 

Trichina    spiralis    Muscles  and   intestines 

Strongylus  paradoxus   Trachea  and  bronchi 

Sclerostoma  pingencola Renal  fat  and  kidney 

Poultry 

Species  Organ 

Ascaris   inflexa    Intestine 

Spiroptera  hamulosa   Gizzard 

rieterakis  papillosa   Caecum 

Syngamus  tracheal  is    Trachea  and  bronchi 

Intestinal  Worms  of  Solipeds. — The  large  round-worms  or 
ascarides  and  the  sclerostomes  are  the  most  injurious  intestinal 
parasites  of  solipeds.     The  A.  megalocephaJa  or  large  round- 
worm is  from  5  to  15  inches  (12  to  35  cm.)  long.     It  may  be 
present  in  the  double  colon  in  such  large  numbers  as  to  form 
an  entangled  mass  that  completely  fills  a  portion  of  the  loop  in 
which  it  is  lodged.    It  may  interfere  with  digestion  by  obstruct- 
ing the  passage  of  alimentary  matter,  and  irritating  the  intestine. 
The  S.  equinum  and  S.  tetracanthum  are  small  worms.    The 
former  sclerostoma  is  from  O.G  to  1.5  inches  (18  to  35  mm.) 
long,  and  the  latter  is  from  0.5  to  0.6  inch  (8  to  17  mm.)  long. 
Both  sclerostomes  attach  themselves  to  the  lining  membrane  of 
the  intestine  by  their  mouth  parts,  and  suck  blood.     The  young 
S.  equinum  may  live  in  tumor-like  cysts  that  they  cause  to  form 
in  the  lining  membrane  of  the  intestine.     The  young  worm  may 
penetrate  the  wall  of  a  small  blood-vessel  as  well,  and  drift 
into  a  large  vessel,  where  it  may  become  lodged  and  undergo 


256  PARASITIC  DISEASES 

partial  development.  The  irritation  to  the  blood-vessel  results 
in  an  inflammation  and  dilation  of  the  vessel  wall.  This  is 
termed  verminous  aneurism.  A  portion  of  the  fibrin-like  lining 
of  the  aneurism  may  flake  off  and  drift  along  in  the  blood  stream, 
until  finally  a  vessel  that  is  too  small  for  the  floating  particle  or 
embohis  to  pass  through  is  reached.  The  vessel  is  then  plugged 
or  a  thrombus  is  formed.  If  the  vessel  involved  by  the  throiubus 
happens  to  be  a  mesenteric  vessel,  then  a  loop  of  intestine  has 
its  blood  supply  cut  off,  and  colicky  pains  result.  Such  colics  are 
dangerous,  and  may  terminate  fatally.  Intestinal  obstruction, 
thrombo-embolic  colics,  unthriftiness  and  a  weakened,  annemic 
condition  may  be  caused  by  intestinal  wonus. 

The  treatment  is  both  preventive  and  medicinal.  The  pre- 
ventive treatment  consists  in  giving  young,  growing  animals 
the  best  care  possible.  Cleanliness  about  the  stable,  giving  the 
colt  plenty  of  range  when  running  in  a  pasture,  and  feeding  a 
ration  that  is  sufficient  to  keep  the  colt  in  good  physical  condition 
are  the  important  preventive  measures.  Tartar  emetic  in  one- 
half  to  one  dram  doses  may  be  given  with  the  feed  daily  until 
five  or  six  doses  are  given.  Turpentine  may  be  given  in  one  to 
three  ounce  doses  in  a  pint  of  linseed  oil.  This  may  be  repeated 
daily  for  two  or  three  days.  Worms  located  in  the  posterior 
bowel  may  be  removed  by  rectal  injections  of  a  weak  water  infu- 
sion of  quassia  chips.  The  rectum  should  be  first  emptied  with 
the  hand,  and  the  nozzle  of  the  syringe  carried  as  far  forward 
with  the  hand  as  possible.  The  injections  should  be  repeated 
daily  for  several  days. 

Intestinal  Worms  of  Cattle. — lutestinal  worms  seldom 
cause  serious  losses  from  unthriftiness  or  death  in  cattle.  It  is 
in  calves  only  that  we  are  called  on  to  treat  this  class  of  disease. 
The  symptoms  resulting  from  the  invasion  of  the  intestinal  tract 
by  the  different  worms  vary  in  severity  according  to  the  number, 
habits  of  the  parasite  and  care  that  the  animal  receives.  The 
usual  symptoms  are  unthriftiness,  indigestion,  diarrhoea  and  a 


ANIMAL  PARASITES  257 

stunted,  aiijrmic  condition.  Stiles  reported  extreme  annnnia, 
nntliriftiness  and  many  deaths  amono;  cattle  in  a  certain  section 
of  Texas,  dne  to  extensive  infection  with  the  Uncinarin  radiatus. 

The  treatment  is  largely  preventive.  Oalves  and  yearlings 
should  be  provided  with  plenty  of  feed  at  all  seasons  of  the  year. 
Good  care  and  careful  feeding  will  keep  them  in  a  thrifty, 
healthy  condition  and  enable  them  to  throw  off  invasions  of 
intestinal  worms.  Turpentine  is  the  vermifuge  usually  admin- 
istered to  calves.  The  dose  is  from  two  to  four  drams  given  in  a 
milk  or  raw  linseed  oil  emulsion. 

Stomach  Worm  of  Sheep. — The  twisted  stomach  worm, 
Hcemonchus  contort  us,  is  the  most  injurious  internal  parasite 
of  sheep.  It  is  a  very  small,  hair-like  worm  from  0.4  to  1  inch 
(9  to  25  mm.)  in  length.  In  the  adult  form  it  attaches  itself 
to  the  mucous  membrane  of  the  fourth  stomach  or  abomasum, 
and  lives  by  sucking  blood.  The  blood  present  in  the  digestive 
tract  of  the  worm  gives  it  a  brown  color,  and  the  white  oviducts 
which  are  wound  around  the  digestive  canal  cause  the  body  to 
appear  twisted.  When  the  twisted  stomach  wonn  is  present  in 
large  numbers,  the  worms  become  mixed  with  the  contents  of  the 
stomach  and  can  be  readily  found  on  making  a  post-mortem 
examination. 

Symptoms  of  stomach  worms  are  first  manifest  in  the 
lambs  (Fig.  76).  It  is  not  until  early  summer  that  the  disease 
appears  in  the  flock.  The  symptoms  are  not  characteristic  un- 
less we  consider  an  unthrifty,  anaemic,  weak,  emaciated  condi- 
tion accompanied  by  diarrha?a  during  the  summer  months  char- 
acteristic of  stomach-worm  disease.  The  sick  animals  are  unable 
to  keep  lip  with  the  flock,  and  they  like  to  stand  about  in  the 
shade.  They  move  slowly,  the  back  is  arched,  the  appetite  poor, 
the  mucous  membranes  and  skin  are  pale  and  the  hind  parts 
soiled  by  the  diarrhoeal  discharge.  More  acute  symptoms  than 
the  above  sometimes  occur.  The  disease  may  last  from  a  few 
days  to  several  weeks.  A  large  percentage  of  the  affected  ani- 
mals die. 
17 


258 


PARASITIC  DISEASES 


The  treatment  is  largely  preventive.  Frequent  changing  of 
pastures  and  dry  lot  feeding  are  common  preventive  measures. 
Permanent  sheep  pastures  lead  to  heavy  losses  from  stomach 
worm  disease.  A  very  effective  preventive  measure,  as  we  may 
term  it,  is  the  practice  of  administering  a  vermifuge  to  the  ewes 
in  the  late  summer  and  again  in  early  winter.  This  may  be 
given  in  a  drench,  or  with  the  feed.  This  prevents  the  reinfec- 
tion of  the  pastures  every  spring,  and  the  young  lambs  are  not 


Via.  76. — Lamb  affected  with  stomach  worm  disease. 

exposed  to  this  form  of  infection.  The  most  effective  treatment 
that  the  writer  has  ever  used  is  the  following  fonnula  recom- 
mended ])y  Dr.  Law:  Arsenous  acid  one  dram,  sulfate  of  iron 
five  drams,  powdered  areca  nut  two  ounces,  common  salt  four 
ounces.  This  is  sufficient  for  one  dose  for  thirty  sheep.  It  may 
be  given  with  the  salt,  or  in  ground  feed.  If  the  flock  is  appar- 
ently healthy,  four  doses  given  at  intervals  of  three  days,,  is 
sufficient.     If  s^nnptoms  of  stomach  worms  are  manifested  the 


ANIMAL  PARASITES  259 

animals  should  be  dosed  daily  until  tiicv  have  received  from  live 
to  ten  doses,  depeudiu*;-  on  the  condition  of  the  animal. 

Intestinal  Worms  of  Sheep. — The  most  widely  distributed 
and  seemingly  most  injurious  intestinal  worm  of  sheep  is  the 
CEsophagodomum  cohimhianum.  It  is  a  small  worm  from  0.5 
to  0.75  inch  (12  to  IS  mm.)  long.  It  penetrates  the  lining  mem- 
brane of  the  intestines  and  encysts  in  the  intestinal  wall.  A 
tumor,  varying  in  size  from  that  of  a  millet  seed  to  a  hazelnut, 
then  forms  in  the  wall  of  the  intestine.  These  tumors  undergo 
a  cheesy  degeneration,  and  when  mature,  may  appear  as  gTeenish, 
cheesy-like  masses,  covering  a  large  portion  of  the  lining  mem- 
brane of  the  intestine.  Diarrhoea  and  emaciation  may  result. 
These  symptoms  are  most  evident  during  the  winter  months. 

The  treatment  recommended  for  ridding  sheep  of  this  in- 
testinal worm  is  largely  preventive.  Very  little  can  be  done 
with  the  medicinal  treatment  of  a  sheep  whose  intestinal  tract  is 
badly  infested  with  this  parasite.  Good  care  and  the  feeding 
of  a  proper  ration  are  the  only  curative  measures  that  are  effec- 
tive in  such  cases.  The  occasional  administration  of  a  vermi- 
fuge for  the  purpose  of  ridding  the  digestive  tract  of  worms, 
together  with  the  frequent  changing  of  pastures  during  the 
spring  and  summer,  are  the  most  effective  preventive  lines  of 
treatment.  The  same  treatment  recommended  for  stomach 
worms  may  be  used  for  this  disease. 

Intestinal  Parasites  of  Hogs. — The  Ascaris  suis  or  common 
round  worm  is  very  commonly  found  in  the  small  intestine.  It 
is  quite  frequently  found  in  large  numbers,  almost  filling  the 
lumen  of  the  intestine  of  an  unthrifty  pig  (Fig.  75).  It  may 
also  work  its  way  into  the  bile  duct.  Sometimes,  after  a  hog  has 
died,  this  parasite  migrates  forward  into  the  stomach  and  gullet. 
The  A.  suis  is  from  4  to  10  inches  (10  to  26  cm.)  long. 

The  Echinorhynchus  gigas  or  thorn-headed  womi  is  the 
most  dangerous  of  all  intestinal  worms  (Fig.  7-i).  It  is  usually 
found  with  its  proboscis  or  thorn  imbedded  in  the  wall  of  the 


260 


PARASITIC  DISEASES 


small  intestine.  The  Echinorhyuclius  is  not  as  common  a  parasite 
as  the  Asearide,  and  it  is  not  usually  present  in  large  numbers. 
Usually,  not  more  than  a  half-dozen  of  these  worms  are  found 
in  the  intestine  of  a  hog,  but  in  some  localities  and  in  hogs  that 
are  allowed  to  root  around  manure  piles  and  in  clover  pastures 
the  herd  may  become  badly  infected  with  them  and  serious 
losses  occur.  The  average  length  of  the  male  is  about  3  inches 
(8  cm.)  and  the  female  10  inches  (26  cm.). 

The  Trichocephalus  crenatus  or  whip  u'orm    (Fig.  77)   is 
slender  or  hair-like  in  its  anterior  two-thirds  and  thick  pos- 


FiG.  77. — Whip-worms  attached  to  wall  of  intestine.         Fig.   78. — Pin  worms  in  iniesuuc. 

teriorly.  It  is  from  1.5  to  2  inches  (40  to  45  mm.)  long.  It 
is  found  in  the  ca?cum  attached  to  the  wall  by  the  hair-like 
portion. 

The  (J^sophagostomum  dcntaium  or  pin  ivorm  is  from  0.3  to 
0.6  inch  (8  to  15  mm.)  long.  It  is  found  in  the  large  intestine 
(Fig.  78). 

The  sijmpiams  of  intestinal  worms  are  not  very  evident  in 
the  average  drove  of  hogs.  Kone  of  the  other  fann  animals  are 
such  common  hosts  for  intestinal  worms  as  hogs.  But  it  is  only 
in  extreme  cases  of  infection  by  intestinal  worms,  and  in  stunted 
and   poorly-cared-for  hogs,   that  very  noticeable  sj-mptoms  of 


ANIMAL  PARASITES  261 

disease  are  manifested.  We  must  not  take  from  tlie  above  state- 
ment that  it  is  unnecessary  to  resort  to  treatment  unless  in  ex- 
ceptional cases.  Intestinal  worms  interfere  with  the  growth  of 
young  hogs,  and  may  irritate  and  inliame  the  intestine,  causing 
chronic  indigestion,  nervous  symptoms,  and  often  death.  This 
irritated  and  inflamed  condition  of  the  intestine  is  best  noted 
in  the  abattoir  by  the  ease  with  which  the  wall  of  the  intestine 
that  contains  large  numbers  of  worms  tears  when  handling  it. 
The  treatment  of  intestinal  worms  in  hogs  is  both  preventive 
and  medicinal.  If  the  conditions  in  the  pens  and  houses  are 
such  as  to  enable  the  eggs  and  embryos  to  live  for  a  long  time, 
or  the  surroundings  are  favorable  for  infection  of  the  animals 
through  their  feed  and  water  supply,  the  herd  may  become  badly 
infested  with  intestinal  parasites.  The  preventive  treatment 
consists  in  keeping  hogs  in  clean,  well-drained  yards  or-  pastures, 
and  feeding  them  from  clean  troughs  and  concrete  feeding  floors 
that  can  be  washed,  when  necessary,  in  order  to  keep  them  clean. 
The  following  vermifuge  can  be  recommended :  Santonin  three 
to  five  grains,  calomel  five  to  eight  grains.  This  is  sufiicient  for 
one  hundred  pounds  weight.  If  the  pigs  are  small  and  it  requires 
two  or  three  to  weigh  one  hundred  pounds,  the  large  dose  should 
be  given.  If  the  hogs  weigh  one  hundred  pounds  or  more,  they 
should  receive  the  small  dose.  The  drove  should  be  divided  into 
lots  of  ten  or  fifteen  hogs  each.  The  drugs  should  be  mixed 
and  divided  into  the  same  number  of  powders  as  there  are  lots 
of  hogs.  Ground  feed  is  placed  in  the  trough,  dampened  with 
milk  or  water,  and  the  powder  sprinkled  evenly  over  it.  The 
hogs  are  then  allowed  to  eat  the  feed.  It  is  best  to  dose  them 
in  the  morning  after  they  have  been  off  feed  for  ten  or  twelve 
hours.  This  vermifuge  may  be  given  in  gelatin  capsules.  A 
small  balling  gun  may  be  used,  or  the  pigs'  mouths  opened  and 
the  capsule  dropped  well  back.  The  dose  is  two  to  three  grains 
each  of  santonin  and  calomel. 


262  PARASITIC  DISEASES 

Verminous  Bronchitis  in  Calves. — The  lung  worms  of  cattle, 
Slrongijlus  micnirus  and  Slrongijlus  pidmonaris,  may  cause 
heavy  losses  in  calves  and  yearlings.  Older  cattle  may  harbor 
these  parasites,  but  they  do  not  seem  to  be  inconvenienced  by 
them.  The  >S'.  micrurus  is  from  1  to  3  inches  (25  to  75  mm.) 
long.  The  S.  j)ulmonaris  is  smaller.  It  is  from  0.4  to  1.3  inches 
(10  to  35  mm.)  long.  They  are  found  in  the  trachea  and  small 
bronchial  tubes,  where  they  are  mixed  with  mucous  secretions 
from  the  inflamed  lining  membrane  of  the  bronchial  tubes. 

Wet  seasons  and  low,  wet  pastures  are  said  to  favor  the 
development  of  lung  worms.  Their  life  history  is  not  fully 
understood.  They  do  not  persist  generation  after  generation 
in  the  air  passages  of  an  animal,  but  the  eggs  and  embryos  are 
expelled  and  live  for  a  time  outside  of  the  animal,  when  they 
may  again  become  parasites  of  another  or  the  same  host. 

The  symptoms  are  the  same  as  occur  in  bronchitis  and  pneu- 
monia. Calves  and  yearlings  are  the  only  animals  in  the  herd 
that  may  show  symptoms  of  the  disease.  The  air  passages  be- 
come irritated  and  inflamed,  and  the  calf  shows  a  slight  cough. 
As  the  inflammation  increases  and  the  worms  and  mucous  secre- 
tions plug  up  the  small  bronchial  tubes,  the  coughing  spells 
become  more  severe  and  rattling,  wheezing  sounds  may  be  heard 
on  auscultating  the  lungs.  The  calf  finally  loses  its  appetite, 
])cconios  emaciated  and  weak,  and  wanders  off  alone.  It  is 
usually  found  lying  down  and  shows  labored  breathing  that  is 
occasionally  interrupted  by  paroxysmal  coughing.  The  death 
rate  in  poorly-cared-for  herds  is  heavy. 

Verminous  Bronchitis  and  Pneumonia  of  Sheep. — The  two 
lung  worms  of  sheep  are  the  Strongyhis  filaria  and  Strongylus 
rufescens.  The  former  is  from  1.3  to  3  inches  (33  to  80  mm.) 
long,  and  the  latter  from  O.G  to  1  inch  (1 G  to  25  mm.)  long.  The 
S.  filaria  is  thread-like  and  the  S.  refuscens  hair-like  in  appear- 
ance. For  this  reason  they  are  termed  thread  and  hair  lung- 
worms.    The  thread-worm  is  found  in  the  trachea  and  the  larger 


ANIMAL  PARASITES  2U3 

bronchial  tubes,  and  the  hair-worm  in  the  most  minute  as  well  as 
the  larger  bronchioli. 

This  disease  is  most  common  in  wet  seasons.  Undrained 
pastures  and  ponds  are  said  to  favor  the  spread  of  the  disease. 
Permanent  pastures  favor  the  reinfection  of  the  flock  from. 
year  to  year.  The  eggs  and  embryos  are  expelled  in  coughing, 
and  live  for  a  time  in  the  pastures,  pens  and  houses.  The  sheep 
become  infected  through  the  dust,  drinking  water  or  feed. 

The  sijmploms  of  vermiuous  hro)ichilis  and  pneumonia  are 
quite  characteristic.  Lambs  suffer  most  from  these  diseases. 
A  number  of  animals  in  the  tlock  are  affected.  ( 'oughing,  rapid 
and  labored  breathing,  loss  of  appetite,  emaciation  and  weak- 
ness are  the  usual  symptoms  noticed.  When  a  paroxysm  of 
coughing  occurs,  considerable  mucus  is  expelled.  An  examina- 
tion of  the  expectorations  may  result  in  finding  a  few  lung 
worms.  In  poorly-cared-for  flocks,  and  when  complicated  by 
stomach  and  intestinal  worms,  the  death  rate  is  usually  heavy. 

The  treatment  of  lung-worm  diseases  in  lambs  and  calves  is 
largely  preventive.  We  should  use  every  possible  precaution 
against  introducing  the  infection  into  the  herd  or  flock.  It  is 
not  advisable  to  bring  animals  from  an  infected  herd  onto  the 
premises,  without  subjecting  them  to  a  careful  examination  and 
a  long  quarantine  before  allowing  them  to  stable  or  pasture  with 
the  other  animals.  Calves  or  lambs  that  show  marked  symptoms 
of  disease  should  be  given  comfortable  quarters,  and  special 
care  and  feeding.  The  entire  herd  or  flock  must  be  given  the 
best  care  and  ration  possible.  This  is  the  only  satisfactory 
method  of  treatment.  Changing  the  pasture  or  lot  frequently 
may  help  in  ridding  the  premises  of  the  infection. 

Verminous  Bronchitis  in  Hogs. — The  lung  worm,  Strongy- 
Jus  paradoxus,  is  a  common  parasite  of  young  hogs.  It  is 
from  0.6  to  1.6  inches  (16  to  40  mm.)  long.  When  the  infec- 
tion is  light,  the  worms  are  found  mostly  in  the  bronchial  tubes 
of  the  margin  and  apex  of  the  lung. 


264  PARASITIC  DISEASES 

Infection  with  this  parasite  does  not  depend  on  the  humiditv 
of  the  soil,  or  low,  wet  pastures  containing  ponds.  Probably 
dusty  quarters  are  responsible  in  large  degree  for  this  disease. 

The  symptoms  are  most  evident  in  pigs  weighing  from  forty 
to  eighty  pounds.  The  first  symptom  is  a  cough,  occurring  on 
leaving  the  bed,  after  exercise  and  after  eating.  In  badly  in- 
fected cases  the  paroxysm  of  coughing  is  quite  severe.  The 
appetite  usually  remains  good  and  the  thriftiness  of  the  pig  is 
not  seriously  interfered  with.  The  feeding  of  a  suitable  ration, 
and  the  good  care  that  is  usually  given  young  hogs,  are  responsible 
for  the  mildness  of  the  disease. 

The  treatment  that  is  of  most  importance  is  clean  quarters, 
and  the  feeding  of  a  ration  that  will  keep  the  pig  growing  and 
healthy.  The  sleeping  quarters  should  be  kept  free  from  dust. 
Disinfectants  should  l)e  used  freely  about  the  quarters. 

The  Kidney  Worm  of  Hogs. — Sclerostoma  pinguicola  is  the 
kidney  worm  of  hogs.  It  is  from  1  to  1.5  inches  (25  to  27  mm.) 
long,  and  when  seen  against  the  kidney  fat  it  appears  dark  or 
mottled.  It  is  usually  found  in  the  fat  in  the  region  of  the 
pelvis  of  the  kidney,  xllthough  the  kidney  worm  is  capable  of 
causing  inflammatory  changes  in  the  tissues  surrounding  the 
kidney  and  the  pelvis  of  this  organ,  the  disease  cannot  be  deter- 
mined by  any  noticeable  symptom.  Paralysis  of  the  posterior 
portion  of  the  body  is  attributed  to  the  presence  of  kidney  worms 
by  stockmen.  There  are  no  data  by  which  we  may  prove  that 
the  kidney  worm  is  responsible  for  this  disorder. 

The  treatment  is  preventive.  Clean  feed,  pens,  watering 
troughs  and  feeding  floors  are  the  preventive  measures  indicated 
here.  It  is  useless  to  attempt  treatment  with  drugs,  as  the  worms 
are  out  of  reach  of  any  drug  that  may  be  administered. 

Worms  of  the  Digestive  Tract  of  Poultry. — Poultry  are 
often  seriously  infested  with  worms.  A  small  number  of  the 
less  injurious  worms  may  not  cause  any  appreciable  symptoms 
of  disease,  but  the  fowl  that  harbors  them  is  a  source  of  infec- 


ANIMAL  PARASITES  265 

tion  to  the  other  fowls.  The  infectious  nature  of  parasitic 
disease  caused  by  worms  should  be  recognized  more  fully  than  at 
present  by  poultrymen. 

The  different  species  of  poultry  are  hosts  for  many  different 
species  of  round-worms,  thorn-headed  worms  and  tapeworms. 
Dr.  Kaupp  states  that  Acaris  infiexa  or  large  round-worm, 
Heterakis  pipilosa  or  small  round-worm,  and  the  Spiroptera 
hamulosa  or  gizzard-worm  are  frequently  found  in  fowls.  The 
common  round-worm  may  be  found  in  the  first  portion  of  the 
intestine,  and  the  small  round-worm  in  the  ca^ca.  Neither 
of  the  species  are  dangerous  unless  present  in  large  numbers. 
They  may  then  obstruct  the  intestine,  and  irritate  the  intestinal 
mucous  membrane.  This  may  cause  constipation,  catarrhal 
inflammation  of  the  intestine  and  diarrhoea.  The  gizzard-worm 
is  the  most  dangerous  of  the  parasites  mentioned.  The  gizzard 
has  an  important  digestive  function,  and  any  condition  that  may 
weaken  its  muscular  walls  may  cause  serious  digestive  disorders. 
This  parasite  may  encyst  in  the  wall  of  the  gizzard. 

The  treatme^it  of  intestinal  worms  in  poultry  is  both  pre- 
ventive and  curative.  The  preventive  measures  consist  in  keep- 
ing the  houses  and  runs  clean.  Air-slaked  lime  should  be 
scattered  over  the  runs  every  few  wrecks.  The  drinking  places 
should  be  cleaned  and  disinfected  daily.  All  possible  precau- 
tions should  be  taken  in  order  to  prevent  filth  from  getting  into 
the  drinking  water.  Epsom  salts,  powdered  areca  nut  and 
santonin  are  the  remedies  commonly  recommended  for  the  treat- 
ment of  intestinal  worms.  From  twenty  to  forty  grains  of 
Epsom  salts  may  be  given.  Powdered  areca  nut  is  recommended 
in  from  three  to  ten  gi-ain  doses.  Santonin  may  be  given  in 
from  one  to  two  grain  doses.  Both  the  areca  nut  and  santonin 
may  be  given  with  the  feed. 

The  Gapes  in  Birds. — The  gape-worm,  Syngamus  tracheaJis, 
is  from  0.2  to  0.8  inch  (5  to  20  mm.)  long.  The  male  and  female 
are  permanently  united.     The  male  is  about  one-third  as  long 


266  PARASITIC  DISEASES 

as  the  female,  and  when  attached  to  the  anterior  third  of  the 
female,  gives  the  pair  a  forked  appearance. 

Fowls  Ijecome  infested  with  the  gape-worm  by  eating  the 
adult  parasite  that  has  been  expectorated,  or  an  earth  worm  that 
is  host  for  the  immature  parasite.  The  embryo  gape-wonn  is 
freed  in  the  intestine,  and  from  here  they  are  supposed  to 
migrate  into  the  abdominal  air  sacs  and  to  the  trachea  and 
bronchi. 

The  sijinptoms  are  most  severe  in  very  young  fowls.  The 
affected  bird  opens  its  mouth  and  appears  to  gasp  for  breath, 
sneeze  and  attemj^t  to  swallow.  In  the  severe  cases  the  appetite 
is  interfered  with,  mucus  accumulates  in  the  mouth  and  the 
bird  is  dull  and  listless.  The  death  rate  is  quite  high  in  young 
chickens   and  turkeys. 

The  treat  mod  is  both  preventive  and  curative.  If  the  gape- 
worm  is  known  to  be  present  in  the  runs,  the  gi'ound  should  be 
covered  with  lime,  and  the  fowls  moved  to  fresh  runs  if  possi- 
ble. The  young  birds  should  not  be  exposed  to  tlie  infection 
until  they  are  well  feathered  out.  Antiseptics  may  be  given 
with  tlie  drinking  water.  Disinfectants  should  be  used  freely 
about  the  poultry  houses,  and  the  quarters  kept  clean.  The 
worms  may  be  snared  by  inserting  a  stiff  horse  hair  that  has 
been  twisted  and  forms  a  loop  into  the  trachea.  This  may  be 
dipped  into  camphorated  oil  or  turpentine.  This  treatment 
should  be  repeated  until  the  bird  has  been  relieved. 

QUESTIONS 

1.  Name  the  difTercnt  groups  of  internal  parasites;  give  examples  of  each. 

2.  What  conditions  favor  liver  rot?     Give  tlie  life  history  of  the  liver  fluke. 

3.  Name  three  common  tapeworms;   give  the  life  history  of  the  beef  and 

pork  tapeworms. 

4.  Name  the  common  intestinal  worms  of  horses  and  give  the  treatment. 

5.  Give  the  symptoms  and  treatment  of  stomach-worm  disease  of  sheep. 

6.  Name  the  common  intestinal  worms  of  hogs  and  give  treatment. 

7.  What  species  of  domestic  animals  suflfer  most  of  verminous  bronchitis? 

Give  the  treatment. 

8.  Name  the  common  internal  parasites  of  poultry  and  give  treatment. 


PART  VI 

INFECTIOUS  DISEASES 


CHAPTER  XXVI 
HOG-CHOLERA 

Hog-cholera  is  a  liiglilv  infectious  disease  of  swine.  It  is 
characterized  by  an  inflammation  of  the  lymphatic  glands,  kid- 
neys, intestines,  lungs  and  skin.  The  inflannnation  is  hemor- 
rhagic in  character,  the  inflamed  organs  usually  showing  deep 
red  spots  or  blotches. 

Ilog-cholera  is  especially  prevalent  in  the  corn-raising  States 
which  possess  a  denser  hog  population  than  any  other  section 
of  the  United  States.  In  this  country  the  loss  from  hog-cholera 
in  1913  amounted  to  more  than  $no.000.000,  and  it  may  be 
considered  of  greater  economic  importance  than  any  of  the  other 
animal  diseases. 

Specific  Cause. — The  specific  cause  of  hog-cholera  is  an 
uUra-visihIe  organism  that  is  present  in  the  excretions,  secretions 
and  tissues  of  a  cholera  hog.  De  Schweinitz  and  Dorset  in  1903 
produced  typical  hog-cholera  by  inoculating  hogs  with  cholera- 
blood  filtrates  that  were  free  from  any  organism  that  could  be 
demonstrated  by  microscopical  examination  or  any  cultural 
method.  The  term  ultra-visible  virus  is  applied  to  the  virus  of 
hog-cholera. 

The  cholera  hog  passes  off  the  virus  with  the  body  excretions. 
Field  data  seems  to  show  that  the  virus  enters  the  body  of  the 
susceptible  hog  with  the  feed  and  drinking  water,  and  that  the 
disease  is  commonly  spread  by  such  indirect  contact  as  shipping 
hogs  in  cholera-infected  cars,  and  visiting  cholera  yards.  The 
surest  method  of  infection  is  by  direct  contact. 

Accessory  Causes. — The  usual  method  of  introducing  hog- 
cholera  into  a  neighborhood  is  through  the  importation  of  feed- 
ing or  breeding  hogs  that  were  infected  with  the  disease  before 

269 


270 


INFECTIOUS  DISEASES 


they  were  purchased,  or  became  infected  through  exposure  to  the 
disease  in  the  public  stock-yards  and  stock-cars.  The  shipping 
of  feeding  hogs  from  one  section  of  the  country  to  another,  and 
from  public  stock-yards,  has  always  been  productive  of  hog- 
cholera.  Dr.  Dorset  states  that  more  than  fifty-seven  per  cent 
of  the  hog-cholera  outbreaks  are  caused  by  visiting,  exchanging 


Fig. 


'0. — A  hug  yard  wht-ru  tin;  diacasc-pruduciug  germs  may   bu  carried  over  from  year 

to  year. 


work,  exposure  on  adjoining  farms  and  harboring  the  infection 
from  year  to  year  (Fig.  79),  and  more  than  twenty-three  per 
cent  to  purchasing  hogs  and  shipping  in  infected  cars,  birds  and 
contaminated  streams. 

In  neighborhoods  where  outbreaks  of  hog-cholera  occur  neces- 
sary precautions  against  the  spread  of  the  disease  are  not  taken. 


HOG-CHOLERA  271 

The  excliange  of  help  at  thresliiiiii;  and  shreddiiiij;'  time  in  noigli- 
borhoods  where  there  is  an  outbreak  of  hog-cholera  is  the  most 
common  method  of  spreading  the  disease.  Visiting  farms  where 
hogs  are  dying  of  cholera ;  walking  or  driving  a  team  and  wagon 
throngh  the  cholera-infected  yards;  stock  buyers,  stock-food  and 
cholera-remedy  venders  that  visit  the  different  farms  in  a  neigh- 
borhood may  distribute  the  hog-cholera  virus  through  the  infected 
filth  that  may  adhere  to  the  shoes,  horses'  feet  and  wagon  wheels. 
Cholera  hogs  may  carry  the  disease  directly  to  a  healthy  herd 
when  allowed  to  run  at  large.  Streams  that  are  polluted  with  the 
drainage  from  cholera-infected  yards  are  common  sources  of 
disease. 

Pigeons,  dogs,  coirs  and  buzzards  that  travel  about  the 
neighborhood  and  feed  in  hog  yards  and  on  the  carcasses  of 
cholera  hogs  may  distribute  the  disease.  Because  of  the  active 
part  that  dogs,  birds  and  surface  drainage  take  in  the  distri- 
bution of  hog-cholera,  the  practice  of  allowing  the  carcasses  of 
dead  hogs  to  lie  on  the  ground  and  decompose  is  responsible  for 
a  large  percentage  of  the  hog-cholera  outbreaks. 

Age  is  an  important  predisposing  factor.  Young  hogs  are 
most  susceptible  to  cholera,  and  this  susceptibility  can  be  greatly 
increased  by  giving  them  crowded,  filthy  quarters.  Infection 
with  lice,  lung  and  intestinal  worms,  the  feeding  of  an  improper 
ration  and  sudden  changes  in  the  ration  lower  the  natural 
resistance  of  a  hog  against  disease.  Pampered  hogs  usually 
develop  acute  cholera  when  exposed  to  this  disease. 

Hog-cholera  is  more  virulent  or  acute  during  the  summer  and 
fall  months  than  it  is  during  the  winter  and  spring  months. 
After  the  disease  sweeps  over  a  section  of  country,  it  becomes 
less  virulent  and  takes  on  a  subacute  or  chronic  form.  Out- 
breaks of  hog-cholera  usually  last  two  or  three  years  in  a  neigh- 
borhood. This  depends  largely  on  the  number  of  susceptible 
hogs  that  were  not  exposed  to  the  infection  the  first  season,  and 
the  preventive  precautions  observed  by  the  owners. 


272  INFECTIOUS  DISEASES 

Period  of  Incubation. — The  length  of  time  elapsing  between 
the  exposure  of  the  hog  to  the  cholera  virus,  and  the  development 
of  noticeable  symptoms  of  hog-cholera,  varies  from  a  few  days 
to  two  or  three  weeks.  The  length  of  this  incubation  period 
depends  on  the  susceptibility  of  the  animal,  the  virulence  of 
the  virus  and  the  method  of  exposure.  An  acute  form  of  hog- 
cholera  indicates  a  short  period  of  incubation,  and  a  chronic 
form,  a  long  period. 

Symptoms. — The  s_>nnptoms  of  hog-cholera  may  differ  widely 
in  the  different  outbreaks  of  the  disease.  The  symptoms  may  be 
classified  under  the  following  forms :  Acute, subacute  and  chronic. 
The  acute  form  of  hog-cholera  is  the  most  common.  The  early 
symptoms  are  tremors,  fever,  depressed  appearance,  marked 
weakness,  staggering  gait,  constipation  and  diarrhoea,  labored 
breathing  and  convulsions.  Death  may  occur  within  a  few  hours 
or  a  few  days.  Recovery  seldom  occurs.  In  the  subacute  form, 
the  symptoms  are  mild  and  develop  slowly.  Recovery  may  take 
place  within  a  few  days,  or  after  extending  over  a  week  or  ten 
days  it  may  assume  the  chronic  form.  Very  often  in  outbreaks 
of  subacute  cholera  a  large  majority  of  the  herd  does  not  show 
visible  symptoms  of  the  disease.  In  the  chronic  form,  marked 
symptoms  of  pleuropneumonia  and  chronic  inflammation  of  the 
intestine  are  common.  Ulcers  and  sores  form  on  the  skin  and 
the  hair  may  come  off.  Large  portions  of  the  skin  may  become 
gangrenous  and  slough.  This  condition  is  caused  by  infection 
with  the  bacillus  necrophorous,  and  is  usually  met  with  in  yards 
that  are  very  insanitary. 

The  first  symptom  of  disease  is  an  elevation  of  body  tem- 
perature. 

At  the  beginning  of  any  outbreak  of  hog-cholera  the  body 
temperatures  of  the  apparently  healthy  animals  may  vary  from. 
105°  to  108°  F.  After  a  few  days,  animals  that  are  fatally 
sick  or  recovering  from  the  disease  may  show  normal  or  sub- 
normal body  temperature. 

Loss  of  appetite  is  the  first  s\anptom  of  disease  usually  noted 


llOCi-CHOLERA  273 

by  the  person  in  cliargc  of  the  herd.  The  hoa'  may  show  a  dis- 
position to  eat  dirt.  The  sick  hog-  is  nsnally  found  lying  in  its 
hed,  or  oli"  by  itself  in  a  quiet  place.  It  presents  a  rather  charac- 
l eristic ^appearance.  The  hack  is  arched,  the  hind  feet  are  held 
close  together,  or  crossed,  the  abdomen  is  tucked  up  and  the  hog 
appears  weak  in  its  hind  parts.  Diarrhaa  or  constipaiion  may 
be  present.  The  color  of  the  diarrhceal  discharges  varies  accord- 
ing to  the  character  of  the  feed,  and  it  may  be  more  or  less  tinged 
with  blood  and  have  a  disagreeable  odor.  The  urine  is  highly 
colored. 

The  respirations  and  pulse  heats  are  quickened  and  abnormal 
in  character.  Thumps  sometimes  occur.  When  the  mucous 
membranes  lining  the  throat  and  anterior  air  passages  are  thick- 
ened, the  respirations  are  noisy  and  difficult.  The  animal  may 
cough  on  getting  up  from  its  bed  and  moving  about.  There  is  at 
times  a  noticeable  discharge  from  the  nostrils.  When  the  Jungs 
are  inflamed  the  respirations  are  quickened  and  labored.  In 
case  the  pleural  membrane  is  inflamed,  the  respiratory  symptoms 
are  more  severe,  and  the  hog  shows  evidence  of  pain  when  the 
walls  of  the  chest  are  pressed  on.  The  pericardium  may  be  in- 
flamed. In  such  eases  the  hog  staggers  and  falls  when  forced 
to  walk. 

The  central  nervous  system  may  be  involved  by  the  inflamma- 
tion. The  usual  symptoms  occurring  in  inflannnation  of  the 
brain  and  its  coverings  are  then  present.  A  sleepy,  comatose 
condition  may  end  in  death,  or  the  animal  dies  in  a  com^ilsion. 

The  secretions  of  the  skin  and  mucous  membranes  are 
al  )normal.  The  skin  in  the  regions  of  the  ears,  inside  of  the  thighs 
and  under  surface  of  the  body  is  moist,  dirty  or  discolored  red. 
Just  before  death  the  skin  over  the  under  surface  of  the  body  be- 
comes a  purplish  red.  In  the  chronic  form,  a  dirty,  thickened, 
wrinkled  skin  is  commonly  observed.  At  first  the  secretion  from 
the  eyes  is  thin  and  watery,  but  it  becomes  thick,  heavy  and  i)us- 
like,  causing  the  margins  of  the  lids  to  adhere  to  each  other. 
18 


274 


INFECTIOUS  DISEASES 


The  death  rate  in  hog-cholera  varies  in  the  different  forms 
of  the  disease.    The  average  death  rate  is  about  fifty  per  cent. 

Differential  Diagnosis. — The  diagnosis  of  hog-cholera  in  the 
field  must  depend  on  the  clinical  symptoms,  post-mortem  lesions 

and  history  of  tlie  outbreak. 
The  history  should  be  that 
of  a  highly  infectious  disease. 
Abnormal  body  tempera- 
tures of  a  large  percentage  of 
the  herd  indicate  the  presence 
of  an  acute  infectious  disease. 
We  should  then  destroy  one 
of  the  sick  hogs  and  make  a 
careful  post-mortem  exami- 
nation (Fig.  80).  An  early 
diagnosis  of  the  disease  is 
necessary,  as  this  enables  us  to 
use  curative  treatment  when 
it  will  do  some  good,  and  take 
the  necessary  steps  toward 
preventing  the  sjjread  of  the 
^  jr  ^^Ai  ^M  '^^^'     disease  to  neighboring  herds. 

^  ^^Bl^^  — i  Intestinal  and  lung  ivorms 

are  common  in  young  hogs. 
The  presence  of  these  worms 
does  not  always  indicate  that 
they  are  the  cause  of  the  sick- 
ness and  death  of  the  animal.  Such  parasites  are  injurious  and 
may  cause  disease,  but  it  is  only  in  rare  cases  that  they  cause 
death. 

"  Pig  typhoid  "  is  sometimes  spoken  of  as  a  highly  infectious 
disease  involving  the  intestines.  A  disease  of  hogs  that  may  be 
termed  typhus-fever  sometimes  affects  a  large  number  of  the 
hogs  in  the  herd.     This  disease  occurs  among  hogs  kept  in  small 


Fig.  80. — Carcass  of  a  rholera  hog  showing 
(A)  different  groups  of  lymphatic  glands;  (B) 
kidneys;  and  (C)  ulcer  on  eeecum. 


HOG-CHOLERA 


275 


yards  and  houses  that  are  crowded,  unsanitary,  and  in  continuous 
use,  or  when  the  hogs  drink  from  wallows,  ponds  and  creeks. 

Infections  pneumonia  or  swine  plague  is  probably  due  to 
insanitary  quarters.  The  symptoms  and  tissue  changes  some- 
times closely  resemble  those  met  with  in  hog-cholera. 

Lesions. — In  acute  hog-cholera  the  inflammation  is  hemor- 
rhagic in  character.  Small,  red  spots  and  blotches  occur  in 
different  organs  and  tissues.  In  the  chronic  form  of  the  disease 
ulceration  of  the  intestinal  and  gastric  mucous  membrane,  in- 


FiG.  81. — Kidneys  from  hog  that  died  of  acute 
hog-cholera. 


Fig.  82. 


-Lungs  from  hog  that  died  of 
acute  hog-cholera. 


flammation  of  the  lungs  and  pleura  and  sloughing  of  the  skin 
are  common  lesions. 

The  shin  over  the  under  side  of  the  neck,  body  and  inside  of 
the  thighs  may  appear  red  or  purplish-red  in  color.  The  different 
groups  of  lymphatic  glands  are  enlarged  and  softened.  They 
may  vary  in  color  from  a  grayish-red  to  a  deep  red,  depending 
on  the  degree  of  engorgement  with  blood.  The  pleura  and  peri- 
cardium may  show  small  red  spots  and  blotches.  The  Tcidneijs  are 
usually  lighter  colored  than  normal,  and  marked  with  red  spots 
and  blotches  (Fig.  81).  The  spleen  may  show  no  evidence  of 
disease.  It  may  be  hemorrhagic,  or  even  smaller  than  normal. 
The  liver  mav  be  enlarged  and  dark,  or  mottled  and  light  colored. 


276 


INFECTIOUS  DISEASES 


The  stomach  and  iniestines  may  show  hemorrhag'ic  spots  and 
blotches.  Sometimes  the  gastric  and  intestinal  nnicons  mem- 
brane is  a  brick  red.  Ulceration  of  the  mucous  membrane  is 
common  (Fig.  83). 

Small,  red  spots  may  be  present  on  the  surface  of  the  lungs 
(Fig.  82).  Scattered  lung  lobules  or  a  large  portion  of  the 
lungs  may  be  inflamed.     In  chronic  hog-cholera^  pleural  exuda- 


Fia.  83. — A  piecL-  ol  intustine  from  a  hog  that  died  of  chronic  hog-cholera,  showing  appear- 
ance of  intestinal  ulcers. 

tion,  adhesions  and  abscesses  in  the  lung  tissue  may  occur.  In- 
flammations of  the  pericardimu  and  heart  muscle  are  less  common 
lesions. 

Preventive  Measures.— Hog-cholera  is  the  most  widespread 
infectious  disease  of  hogs,  and  all  possible  precautions  against  its 
distribution  to  healthy  herds  should  be  practised.  Hogs  coming 
from  other  herds  and  stock  shows  should  be  excluded  from  the 


HOG-CHOLERA  277 

home  herd  until  tliev  are  positively  sliowii  to  be  free  from  dis- 
ease. They  should  be  quarantined  in  yards  set  oft'  for  this  pur- 
pose. The  hogs  should  be  cleaned  by  dipping  or  washing  them 
with  a  disinfectant.  The  quarantine  period  should  be  longer 
than  the  average  ^^eriod  of  incubation.    Three  weeks  is  sufficient. 

The  possible  inirodudioii  of  the  disease  into  the  pens  by 
people,  dogs,  birds  and  other  carriers  of  the  disease  should  be 
guarded  against,  especially  if  cholera  is  present  in  the  neighbor- 
hood. The  exchange  of  help  at  threshing  and  shredding  time 
with  a  neighbor  who  has  hog-cholera  on  his  farm  is  a  common 
method  of  distributing  the  infection.  It  is  not  advisable  to  allow 
a  stranger  to  enter  your  hog-houses  and  yards,  unless  his  shoes 
are  first  disinfected.  Whenever  it  is  necessary  for  a  person  to 
enter  yards  where  the  disease  is  present,  the  shoes  should  be 
cleaned  and  disinfected  on  leaving.  The  wheels  of  wagons,  and 
the  feet  of  horses  that  are  driven  through  cholera  yards,  should 
be  washed  with  a  disinfectant.  The  feet  of  feeding  cattle  that 
are  shipped  from  stock-yards  should  be  treated  in  the  same  man- 
ner. Persons  taking  care  of  cholera  hogs  should  observe  the 
necessary  precautions  against  the  distribution  of  the  disease,  and 
see  that  others  practise  like  precautions. 

Ilog-yards  should  be  well  drained  and  all  wallow  holes  filled. 
Pens  and  pastures  through  which  the  drainage  from  the  swine 
enclosures  higher  up  flows  should  not  be  used  for  hogs. 

Care  o£  a  Diseased  Herd. —  When  an  outbreak  of  hog-cholera 
occurs  on  a  farm  the  farm  should  be  quarantined.  The  herd 
should  be  moved  away  from  running  streams,  public  roads  and 
line  fences,  so  that  neighboring  herds  are  not  unnecessarily  ex- 
posed to  the  disease.  During  the  hot  weather  shade  and  an  oppor- 
tunity to  range  over  a  grass  lot  or  pasture  are  highly  necessary. 
A  recently  mowed  meadow,  or  a  blue  grass  pasture  and  a  low 
shed,  open  on  all  sides  and  amply  large  for  the  herd  to  lie  under, 
give  the  animals  clean  range  and  comfortable,  cool  quarters. 
Eoomy,  dry,  well-ventilated  sleeping-cjuarters  that  are  free  from 


278 


INFECTIOUS  DISEASES 


drafts  and  can  be  cleaned  and  disinfected  are  best  when  the 
weather  is  cold  and  wet. 

In  the  subacute,  and  in  the  early  part  of  an  acute  outbreak 
of  hog-cholera,  it  is  advisable  to  separate  the  sick  from  the  well 
hogs.    The  fatally  sick  animals  should  be  destroyed. 

A  very  light  ration  should  be  fed  and  an  intestinal  antiseptic 
given  with  the  feed.  A  thin  slop  of  shorts  is  usually  preferred. 
Four  ounces  of  pulverized  copper  sulfate  may  be  dissolved  in  one 
gallon  of  hot  water,  and  one  quart  of  this  solution  may  be  added 


Fig.   si. — t'li-aning  up  a  hog  lot, 

to  every  ten  gallons  of  drinking  water  and  slop.  Water  and  slop 
should  not  be  left  in  the  troughs  for  the  hogs  to  wallow  in.  The 
troughs  should  be  disinfected  and  turned  bottom  side  up  as 
soon  as  the  hogs  have  finished  feeding  and  drinking.  Kitchen 
slop  and  sour  milk  should  not  be  fed.  The  care  and  treat- 
ment of  the  herd  require  work  and  close  attention  on  the  part 
of  the  attendant.  Indifferent,  careless  treatment  is  of  no  use 
in  this  disease. 

A  disinfectant  should  be  sprayed  or  sprinkled  about  the 
feed  troughs,  floors,  pens  and  sleeping  quarters  daily. 


HOG-CHOLERA  279 

Disposing  of  Dead  Hogs.— The  carcasses  of  the  dead  liogs 
should  be  burned.  Before  placing  the  carcass  on  the  fire,  it 
should  be  cut  open  and  several  long  incisions  made  through  the 
skin.  A  crematory  niav  be  made  by  digging  two  cross  trenches 
that  are  about  one  foot  deep  at  the  point  where  they  cross,  and 
shallow  at  the  ends.  Iron  bars  or  pipe  may  be  laid  over  the 
trenches  where  they  cross  for  the  carcass  to  rest  upon,  or  woven 
wire  fencing  securely  fastened  with  stakes  may  be  used  in  the 
place  of  the  iron  bars.  If  the  carcass  is  disposed  of  by  burying, 
it  should  be  buried  at  least  four  feet  deep  and  covered  with 
quicklime. 

Disinfecting  the  Yards  and  Houses.— If  the  sick  hogs  are 
moved  to  new  quarters  at  the  beginning  of  the  outbreak,  the  hog 
houses  and  yards  should  be  cleaned  and  disinfected  (Fig.  84). 
The  manure  and  all  other  litter  should  be  hauled  away  to  a  field 
where  there  is  no  danger  from  this  infectious  material  becoming 
scattered  about  the  premises,  leaving  a  centre  of  infection  in  the 
neighborhood  and  causing  outbreaks  of  cholera  among  neighbor- 
ing herds.  It  may  be  advisable  to  burn  the  corn-cobs  and  other 
litter  that  have  accumulated  about  the  yards.  Loose  board  floors 
should  be  torn  up  and  the  manure  from  beneath  removed. 
Portable  houses  should  be  removed.  The  floors,  walls  of  the 
house  and  fences  should  be  first  cleaned  by  scraping  off  the  filth, 
and  then  sprayed  with  a  three  per  cent  water  solution  of  a  cresol 
or  coal  tar  disinfectant  to  which  sufficient  lime  has  been  added 
to  make  a  thin  whitewash.  Three  or  four  months  of  warm,  sunny 
weather  are  sufficient  to  destroy  the  cholera  infection  in  well- 
cleaned  yards. 

Anti-hog-cholera  Serum. — The  credit  of  developing  the  first 
and  at  present  the  only  reliable  anti-hog-cholera  serum  and 
method  of  vaccination  belongs  to  Drs.  Dorset  and  ]^iles.  Anti- 
hog-cholera  serum  came  into  general  use  in  1908,  and  all  of  the 
swine-producing  States  have  established  State  laboratories  for 
the  production  of  this  serum. 


280 


INFECTIOUS  DISEASES 


Anti-Log-eholcra  serum  is  produced  by  injecting  directly,  or 
indirectly,  into  the  blood-vessels  of  an  immune  hog  a  large  quan- 
tity of  cholera  virus,  secured  by  bleeding  a  hog  that  is  fatally 
sick  with  acute  cholera,  and  bleeding  the  injected  animal  after 
it  has  completely  recovered  from  the  injection.  The  injection 
of  the  cholera  blood  is  for  the  purpose  of  stimulating  the  produc- 
tion of  antibodies  by  the  body  tissues,  and  raising  the  protective 
properties  of  the  immune  hog's  blood.  An  animal  so  treated  is 
called  a  hyperimmune  (Fig.  85).  The  blood  from  the  hyper- 
immunes is  defibrinated  and  a  preservative  added,  and  after  it 


Fig.   85. — Hyperimmune  hogs  used  for  the  production  of  anti-hog-cholera  serum. 

has  been  tested  for  potency  and  freedom  from  contaminating 
organisms,  it  is  ready  for  use. 

The  Vaccination  of  Hogs  with  Anti-hog-cholera  Serum. — 
The  vaccination  of  a  hog  by  the  single  method  consists  in  inject- 
ing hypodermically  or  intramuscularly  anti-hog-cholera  serum. 
The  immunity  conferred  may  not  last  longer  than  three  or  four 
weeks. 

The  vaccination  of  a  hog  by  the  dnuhle  method,  consists  in 
injecting  hypodermically  or  intramuscularly  anti-hog-cholera 
serum  and  hog-cholera  blood. 

The  vaccination  or  treatment  of  a  cholera  hog  showing  notice- 


HOG-CHOLERA 


281 


able  s^^llptoms,  or  a  liiiili  bodj  temperature,  consists  in  injecting 
hypodermlcally  or  intramuscularly  anti-liog-cliolera  serum  (Fig. 
87). 

TJie  region  into  wliieli  the  serum  and  cholera  blood  may  be 
injected  are  the  inside  of  the  thigh,  within  the  arm,  flank  and 
side  of  the  neck  (Fig.  86).     Two  hypodermic  syringes,  holding 


Fig.  86. — Preparing  the  hog  for  vaccination 
by  washing  the  part  where  the  serum  is  in- 
jected with  a  disinfectant. 


Fig.  S7. — Vaccinating  a  hog. 


about  twenty  cubic  centimetres  and  six  cubic  centimetres,  and 
having  short,  heavy,  seventeen  or  eighteen-gauge  slip-on  needles, 
should  be  used.  The  small  syringe  is  used  for  injecting  the  viru- 
lent or  cholera  blood  w^hich  is  injected  into  a  different  part  than 
the  serum.  The  quantity  of  serum  and  virus  injected  varies 
with  the  size  and  condition  of  the  animal.     Young  hogs  should 


282  INFECTIOUS  DISEASES 

receive  one-half  eubic  centimetre  of  serum  for  each  pound  of 
body  weight,  and  cholera  hogs  should  be  given  one-half  more  to 
twice  the  dose  that  is  recommended  for  healthy  animals.  To 
establisli  permanent  immunity  not  less  than  two  cubic  centimeters 
of  hog-cholera  blood  should  be  given. 

In  vaccinating  small  pigs  not  more  than  five,  and  in  large 
hogs  not  more  than  twenty,  cubic  centimetres  should  be  injected 
at  any  one  point.  The  hody  temperature  of  each  animal  should 
be  taken.  A  body  temperature  of  103.5°  F.  in  a  mature  hog 
and  a  body  temperature  of  104°  F.  in  a  young  hog  may  indicate 
hog-cholera.  Exercise,  feeding  and  close  confinement  in  a  warm 
place  may  raise  the  body  temperature  above  the  normal. 

Hogs  that  are  to  be  vaccinated  or  treated  should  not  be  given 

feed  for  at  least  twelve  hours  before  handling  them.    If  possible 

they  should  be  confined  in  a  roomy,  clean,  well-bedded  pen.     If 

this  is  practised,  they  are  cleaner  and  easier  to  handle  and  their 

body  temperatures  are  less  apt  to  vary.     After  the  treatment  or 

vaccination  the  hogs  should  be  fed  a  light  diet  for  a  period  of  at 

least  ten  days,  and  the  ration  increased  gradually  in  order  to 

avoid  causing  acute  indigestion.     This  is  necessary  because  of 

the  elevation  in  body  temperature  resulting  from  the  inability 

of  the  animal  to  digest  heavy  feeds,  kitchen  slops  and  sour  milk. 

If  poor  judgment  is  used  in  caring  for  the  vaccinated  hogs,  and 

the  person  who  vaccinates  them  uses  careless  methods,  heavy 

losses  from  acute  indigestion,  blood  poisoning,  or  hog-cholera 

may  occur. 

QUEISTIONS 

1.  What  is  the  specific  cause  of  hog-cholera?    Give  and  describe  the  different 

methods  of  spreading  the  disease. 

2.  What  are  the  symptoms  of  hog-cholera? 

3.  Give  the  preventive  and  curative  treatment  of  liog-cholera. 

4.  What  is  anti-hog-cholera  serum?     Give  the  different  methods  of  vaccina- 

tion and  treatment. 


CHAPTER  XXVII 
TUBERCULOSIS 

TuBEKCULOsis  IS  a  contagious  and  infectious  disease  of  man 
and  domestic  animals,  affecting  any  body  tissues,  but  esi)ecially 
the  lymphatic  glands  and  lungs.  The  characteristic  diseased 
change  in  the  tissues  is  the  fonnation  of  the  tubercle  or  nodule. 

History. — Tuberculosis  is  one  of  the  oldest  of  known  diseases 
of  domestic  animals  and  man.    Its  contagious  and  infectious  char- 
acter was  proven  by  Villeniin  in  1S05,  who  by  experimental  in- 
fection transmitted  tuberculosis  from 
man  to  animals  and  from  animal   to 
animal.     It  was  in  1882  that  Dr.  Rob- 
ert Koch  discovered  and  proved  by  in- 
oculation experiments  that  the  disease 
was  caused  by  a  specitic  genu   (Fig. 
88).  Prior  to  the  experiments  by  Ville- 
min  and  Koch,  the  belief  was  that  tuber- 
culosis was  due  to  heredity,  unsanitary 
conditions  and  inbreeding.      Following      ^^°-  ss.— Koch's  Badiius  tuber- 

culosis. 

discovery  of  the  specific  germ  and  con- 
ditions favoring  its  development  and  sjiread,  numerous  scientifi- 
cally conducted  experiments  were  made.  These  have  resulted  in 
practical  methods  of  control  and  elimination  of  tuberculosis  from 
herds  having  tliis  disease.  By  carefully  conducted  experi- 
ments and  other  forms  of  educational  work  the  infectious  charac- 
ter of  tuberculosis  and  the  economic  importance  of  preventive 
measures  have  been  demonstrated.  The  average  stockman 
is  well  informed  regarding  the  character  and  economic  impor- 
tance of  this  disease,  but  there  is  no  general  application  of  this 
knowledge,  and  tuberculosis  is  increasing  in  dairy  and  breeding 
herds.     The  slow  development  of  tuberculosis,  and  tlie  absence  of 

283 


284  INFECTIOUS  DISEASES 

visible  symptoms  duriiip;  the  early  stage  of  the  disease,  are 
responsible  for  this  condition  and  the  extensive  infection  of  dairy 
and  breeding'  herds. 

Prevalence  of  the  Disease. — Tuberculosis  is  very  prevalent 
among  cattle  and  swine  in  all  countries  where  intensive  agricul- 
ture is  practised.  It  is  a  rare  disease  among  cattle  of  the  steppes 
of  eastern  Europe  and  the  cattle  ranges  of  the  western  portion 
of  the  United  States.  In  countries  where  dairying  is  an  im- 
portant industry,  tuberculosis  is  a  common  disease  of  cattle  and 
hogs.  The  abattoir  reports  of  Europe  and  the  United  States 
show  that  tuberculosis  is  on  the  increase  among  domestic  animals. 
The  Bureau  of  Animal  Industry  of  the  United  States  Depart- 
ment of  Agriculture  reports  that  out  of  400,008  cattle  tested  with 
tuberculin  9.25  per  cent  reacted.  jMelvin  states  that  the  annual 
loss  from  tuberculosis  in  the  United  States  is  about  $23,000,000. 
In  dairy  herds  in  which  the  disease  has  existed  for  several  years,  it 
is  not  uncommon  to  find  from  25  to  75  per  cent  tubercular. 

The  Direct  Cause. — The  direct  cause  of  tuberculosis  is  Koch's 
Bacillus  tuberculosis.  This  is  a  slender,  rod-shaped  microorga- 
nism (Eig.  88)  occurring  in  the  diseased  tissues,  faeces  and  milk 
of  a  tubercular  animal.  It  belongs  to  that  small  group  knoA\Ti  as 
acid-fast  bacteria.  The  tubercle  bacillus  is  not  really  destroyed 
by  external  influences,  and  it  may  retain  its  virulence  for  several 
months  in  dried  sputum  if  protected  from  the  light.  Its  vitality 
enables  it  to  resist  high  temperatures,  changes  in  temperature, 
drying  and  putrefaction  to  a  greater  degree  than  most  non-spore- 
producing  germs.  Direct  sunlight  destroys  the  germ  within  a  few 
hours,  but  it  may  live  in  poorly  lighted,  filthy  stables  for  months. 
A  temperature  of  65°  C.  destroys  it  in  a  few  minutes. 

Animals  that  have  advanced  or  o]ien  tuberculosis  may  dis- 
seminate the  germ  of  the  disease  in  the  discharge  from  the 
mouth,  nostrils,  genital  organs,  in  the  intestinal  excreta  and  milk. 
The  germs  discharged  from  the  mouth  and  nostrils  are  coughed 
up  from  the  lungs  and  may  infect  the  feed.     Milk  is  a  common 


TUBERCULOSIS  285 

source  of  infection  for  calves  and  liog-s.  Allowing  hogs  to  run 
after  cattle  is  sure  to  result  in  infection  of  a  large  percentage  of 
them,  if  there  are  any  o^oen  cases  of  tuberculosis  in  the  herd. 

Predisposing  Causes. — Any  condition  that  may  lessen  the 
resistance  of  the  body  or  enable  the  tubercle  bacillus  to  survive 
the  exposure  outside  the  body  favors  the  development  of  the 
disease  and  the  infection  of  the  healthy  animals.  Crowded, 
poorly  ventilated,  filthy  stables  lower  the  disease-resisting  power 
of  the  animal,  and  favor  the  entrance  of  the  germs  into  the  body. 
Under  such  unsanitary  conditions,  tuberculosis  spreads  quickly 
among  dairy  cattle,  and  a  large  percentage  of  the  animals  de- 
velop the  generalized  form  of  the  disease.  Sanitary  stables  and 
yards  do  not  prevent  the  spread  of  the  disease  among  animals 
that  live  in  close  contact  with  one  another.  Fresh  air  and  sani- 
tary surroundings  only  check  the  spread  and  retard  its  progress. 

Introduction  of  Tuberculosis  into  the  Herd. — The  common 
method  of  introducing  tuberculosis  into  the  herd  is  through  the 
purchase  of  animals  having  the  disease.  Such  animals  may  be 
in  apparent  good  health  at  the  time  of  purchase,  and  be  affected 
with  generalized  or  open  tuberculosis. 

A  source  of  infection  is  by  unknowingly  buying  cows  that 
have  reacted  to  the  tuberculin  test.  The  indiscriminate  use  and 
sale  of  tuberculin  are  largely  responsible  for  the  large  number 
of  reacting  animals  that  have  been  placed  on  the  open  market. 
This  dishonest  practice  has  resulted  in  the  rapid  spread  of  the 
disease  in  certain  localities.  For  years  a  large  percentage  of 
the  l)reeding  herds  have  been  infected,  and  the  writer  has  met  with 
several  herds  of  dairy  and  beef  cattle  that  became  tubercular 
through  the  purchase  of  tubercular  breeding  animals. 

Symptoms. — There  is  no  one  symptom  by  which  w^e  may 
recognize  tuberculosis  in  cattle  and  hogs.  ISTone  of  the  symptoms 
shown  by  a  tubercular  animal  are  characteristic,  unless  it  is  in 
the  late  stage  of  the  disease.  In  a  well-cared  for  animal,  the 
lymphatic  glands  iu  the  different  regions  of  the  body,  the  lungs, 


286 


INFECTIOUS  DISEASES 


liver  and  other  organs,  may  be  full  of  tubercles  without  causing 
noticeable  symptoms  of  disease  (Fig.  89), 

Tuberculosis  may  attack  any  organ  of  the  body,  and  in  the 
different  cases  of  the  disease  the  symptoms  may  vary.  Enlarge- 
ment of  the  glands  in  the  region  of  the  throat,  and  noisy,  difficult 
breathing  are  sometimes  present.  The  udder  frequently  shows 
hard  lumps  scattered  through  the  gland.  Bloating  may  occur 
if  a  diseased  gland  in  the  chest  cavity  presses  on  the  oesophagus 


Fig.  89. — Cows  affected  with  tuberculosis.      Many  cows  having  generalized  tuberculosis  are 
not  found  out  until  tuberculin  tested. 

and  prevents  the  usual  passage  of  gas  from  the  paunch.  Chronic 
diarrhd'a  may  occur.  If  the  disease  involves  the  digestive  tract, 
the  animal  is  unthrifty  and  loses  flesh  rapidly.  Coughing  is  not 
a  characteristic  symptom,  and  we  should  not  place  too  much 
emphasis  on  it.  If  the  lungs  become  tubercular  the  animal 
usually  has  a  slight,  harsh  cough.  The  cough  is  first  noticed  when 
the  cattle  get  up  after  lying  down,  when  the  stable  is  first 
opened  in  the  morning  and  when  the  animals  are  driven.  If 
the  chest  walls  arc  thin,  soreness  from  pressure  on  the  ribs  may 


TUBERCULOSIS 


287 


be  noted.  By  applying  the  car  to  the  chest  wall  and  listening 
to  the  lung  sounds,  absence  of  respiratory  inni'iinirs  and  abnor- 
mal sounds  may  be  distinguished,  duo  to  consolidation  of  tho 
lung  tissue,  abscess  cavities  and  pleural  adhesions.  In  a  well- 
advanced  case  the  hair  is  rough,  the  skin  becomes  tight  and  the 
neck  thin  and  lean.  The  animal  may  breathe  through  the  mouth 
when  it  is  exercised.    Weakness  may  be  a  prominent  symptom. 

Breeding  animals  that  are  well  fed  and  cared  for  may  live 
for  several  years  before  showing  noticeable  s\Tnptoms  of  tuber- 


FiG.  90. — Tubercular  spleens. 

culosis.  The  disease  progresses  more  rapidly  in  milch  cows,  espe- 
cially if  given  poor  care.  Calves  allowed  to  nurse  a  tubercular 
mother  that  is  giving  off  tubercle  bacilli  frequently  develop 
enlarged  throat  glands  and  the  intestinal  form  of  the  disease. 

Hogs  develop  a  generalized  form  of  tuberculosis  more  quickly 
than  cattle,  but  an  unthrifty,  emaciated  condition  is  seldom 
noted  in  hogs  under  ten  months  old. 

Post-mortem  Lesions. — The  effect  of  the  tubercle  bacilkis 
on  the  body  is  to  irritate  and  destroy  the  tissues.  Lumps  or 
tubercles  form  in  the  l;)Tnphatic  glands,  liver,  lungs,  spleen  (Fig. 


288 


INFECTIOUS  DISEASES 


90),  serous  membranes,  kidneys  and  other  body  organs  (Figs. 
91  and  92).     The  tnherclos  may  be  very  small  at  first,  but  as 


FlQ.  91. — The  carcass  of  a  tubercular  cow.      Note  the  condition  of  the  carcass,  and  the 
tubercular  nodules  on  the  chest  wall,  showing  that  the  disease  was  well  advanced. 

the  disease  progresses  they  continue  to  enlarge  until  finally  a 
tubercular  mass  the  size  of  a  base-ball,  or  larger,  is  formed 
(Figs.   93,  94,  95  and  96).     Lymphatic  glands  may  become 


TUBERCULOSIS 


289 


several  times  larger  tluin  iiorinal  and  tlie  liver  and  lungs  greatly 
enlarged.  The  pleura  and  peritoneum  may  bo  thickened  and 
covered  with  tubercles  about  the  size  of  a  millet  seed,  or  larger. 
Pleural  and  peritoneal  adhesions  to  the  organs  within  the  body 
cavities  are  common. 

The  tubercle  usually  undergoes  a  cheesy  degeneration.  Old 
tubercles  may  become  hard  and  calcareous.  Sometimes  the  cap- 
sule of  the  tubercle  is  filled  with  pus.     A  yellowish,  cheesy 


Fig.  92.— a  section  of  the  chest  wall  of  a  tubercular  cow  showing  a  better  view  of  the 

diseased  tissue. 

material  within  the  capsule  of  the  tubercular  nodule  or  mass  is 
typical  of  the  disease. 

The  Tuberculin  Test. — The  only  certain  method  of  recogniz- 
ing tuberculosis  is  by  this  test.  There  is  no  other  method  of 
recognizing  this  disease  that  is  more  accurate  than  the  above  test. 

The  substance  used  in  testing  animals  for  tuberculosis  is  a 
laboratory  product.  It  is  a  germ-free  fluid  prepared  by  growing 
the  tubercle  bacillus  in  cultiu'e  medium  (bouillon)  until  charged 
19 


290 


INFECTIOUS  DISEASES 


with  the  toxic  products  of  their  growth.  The  culture  medium  is 
then  heated  to  a  boiling  temperature  in  order  to  destroy  the 
germs.  It  is  then  passed  through  a  porcelain  filter  that  removes 
the  dead  germs.    The  remaining  fluid  is  tuberculin. 

Tliere  are  iliree  methods  of  applying  the  tuberculin  test.     Tlie 


flQ.   93. 


-A  very  large  tubercular  gland  that  had  broken  down  in  the  central   portion. 

subcutaneous  test  consists  in  injecting  a  certain  quantity  of  tuber- 
culin beneath  the  skin,  and  keeping  a  record  of  the  body  tem- 
perature of  the  animal  l^etween  the  eighth  and  eighteenth  hours 
following  the  injection.  Tubercular  animals  show  an  elevation 
in  temperature  that  comes  on  about  the  eighth  or  twelfth  hour  of 
the  test.  In  the  intradermal  test,  a  small  quantity  of  a  special 
tuberculin  is  injected  into  the  deeper  layer  of  the  skin.  The  seat 
of  the  injection  in  cattle  is  a  fold  of  the  skin  on  the  under  side 


TUBERCULOSIS 


291 


of  the  base  of  the  tail. 
In  tubercular  auinials 
the  injection  is  followed 
by  a  characteristic  local 
swelling.  The  ophthal- 
mic test  is  sometimes 
used. 

The  control  of  tu- 
berculosis is  largely  in 
the  hands  of  the  breeder 
and  dairyman.  This  is 
a  disease  that  requires 
the  cooperation  of  stock- 
men and  sanitary  offi- 
cers in  the  application 
of  control  measures.  If 
there  are  several  open 
cases  of  tuberculosis  in 
a  herd  of  cattle,  the  ap- 
plication of  the  tubercu- 
lin test,  removal  of  the 
reacting  animals  and 
disinfection  of  the 
premises  are  not  suffi- 
cient to  eradicate  the 
disease.  It  is  necessary 
to  repeat  the  tuberculin 
test  wathin  six  months, 
and  later  at  twelve- 
month intervals,  until 
none  of  the  animals  that 
remain  in  the  herd  re- 
act. ■ 

The   most  practical 


Fig.  94. — A  tubercular  gland  that  is  split  open. 


Fig.  95. — Caul  showing  tuberculosis. 


Fig.  96. — Foot  of  hog  showing  tuberculosis  of  joint. 


292  INFECTIOUS  DISEASES 

method  of  disposing  of  dairy  cows  tliat  react  to  the  tiTberculin 
test  is  to  slaughter  them.  Unless  a  large  percentage  of  the 
herd  is  ti;bercular,  it  is  not  advisable  to  practise  segregation 
and  quarantine.  This  may  be  advisable  if  the  reactor  is  a 
valuable  breeding  animal,  unless  visible  symptoms  are  shown. 
The  milk  from  reacting  cows  may  be  used  if  it  is  boiled  or  steril- 
ized. Whenever  a  calf  is  born  of  a  reactor,  it  should  be  separated 
from  the  mother  and  fed  milk  from  a  healthy  cow. 

The  separation  of  the  tubercular  from  the  healthy  cows  must 
be  complete.  Sej)arate  buildings,  yards  and  pastures  that  do  not 
join  the  quarters  where  the  healthy  animals  are  kept  should  be 
provided.  The  person  attending  the  reactors  should  not  attend 
the  healthy  animals,  and  separate  forks,  shovels,  pails  and  other 
utensils  should  be  provided  for  the  two  herds. 

*  The  best  method  of  controlling  tuberculosis  in  hogs  is  to 
slaughter  all  reactors,  disinfect  yards  and  liouses  and  move  the 
herd.  If  the  old  quarters  are  free  from  filth  and  carefully  disin- 
fected, the  hogs  may  be  returned  without  danger  of  infection 
after  six  months.  A  retest  of  the  herd  should  be  made  before 
returning  them  to  the  permanent  quarters  and  the  reactors 
slaughtered. 

In  the  principal  stock  raising  states  accredited  or  tubercular- 
free  breeding  herds  are  becoming  common.  This  has  been  made 
possible  by  large  federal  appropriations  of  funds  for  the  eradica- 
tion of  tuberculosis.  This  is  the  most  effective  method  that 
has  been  used  in  the  eradication  of  this  disease. 

QUESTIONS 

1.  Give  tlie  history  of  the  early  experimental  work  in  tubereiilosis ;  give  the 

common  mctliods  of  spreading  the  disease. 

2.  What  are  the  symptoms  and  post-mortem  lesions  in  tuberculosis? 

3.  Give  the  method  of  controlling  tuberculosis. 


CHAPTER  XXVIII 

INFECTIOUS    DISEASES    COMMON    TO    THE    DIFFERENT 
SPECIES  OF  DOMESTIC  ANIMALS 

Septicaemia  and  Pyaemia. — The  term  commonly  used  in 
speaking  of  simple  septicaemia  and  pyaomia  is  blood  poisoning. 

These  infections  diseases  are  caused  by  several  different 
species  of  bacteria  that  gain  entrance  to  the  tissnes  by  way  of 
wounds.  The  bacteria  that  cause  pyaemia  are  transferred  by  the 
blood  stream  to  different  organs  and  prodnce  nniltiple  abscesses. 
Tn  septicaemia,  the  bacteria  may  occur  in  immense  numbers  in 


Fig.  97. — Stap/iyluco^cus  piiogenes.         Fig.  98. — Streptococcus  pyogenes. 

the  blood  and  produce  a  general  infection  of  the  tissues,  causing 
a  parboiled  appearance  of  the  liver,  heart,  voluntary  muscles  and 
kidneys,  and  enlargement  of  the  spleen.  The  two  forms  of  infec- 
tion are  often  present  at  the  same  time. 

The  forms  of  bacteria  that  may  cause  blood  poisoning  are 
the  Staphylococcus  pyogenes  aureus  and  albus  (Fig.  97),  Strep- 
tococcus pyogenes  (Fig.  9S),  BarUlus  pyocyaneus.  Bacillus  coli 
communis,  and  the  bacillus  of  malignant  oedema  (Figs.  99  and 
100).  The  latter  is  included  with  the  bacteria  that  produce  blood 
poisoning  because  it  is  a  frequent  cause  of  wound  septicaemia. 
Subcutaneous,  punctured,  lacerated,  contused  and  deep  wounds 
without  suitable  drainage  are  the  most  suitable  for  the  develop- 

293 


294 


INFECTIOUS  DISEASES 


ment  of  and  infection  of  the  tissues  with  the  above  germs. 
Wound  infection  is  most  connnon  during  hot  weather. 

The  symptoms  are  both  general  and  local.  The  tissues  in 
the  region  of  the  wound  become  swollen  and  painful.  In  malig- 
nant a'dema  the  swelling  pits  on  pressure,  and  if  the  wound  is 
open,  the  surface  becomes  soft  and  may  slough.  The  body 
temperature  may  be  several  degrees  above  the  normal,  the  appe- 
tite is  impaired  or  the  animal  stops  eating  and  acts  sleepy.  A 
small  amount  of  highly-colored  urine  may  be  passed.  Ner,'ous 
symptoms,  such  as  muscular  twitching,  excited  condition,  de- 
lirium and  paralysis,  may  be  noted. 


FlQ.  99. — Bacillus  of   malignant 
cedema,  showing  spores. 


Fia.    100. — Bacillus  of  malignant 
oedema. 


The  -prognosis  is  unfavorahle.  In  pysrmia  the  animal  may 
live  from  a  few  days  to  several  months.  Septicemia  usually 
terminates  fatally  in  from  t\vo  to  ten  days. 

The  treatment  is  largely  preventive.  Wounds  should  be 
given  prompt  attention.  They  should  be  freed  from  all  foreign 
substances  and  washed  with  a  disinfecting  solution.  A  contused- 
lacerated  wound  should  not  be  sutured  if  this  interferes  with  the 
cleansing  of  it,  and  the  escape  of  the  wound  secretions.  All 
punctured  wounds  should  be  enlarged  so  as  to  permit  of  treat- 
ment and  drainage. 

Hemorrhagic  Septicemia. —  An  acute  infectious  disease  of 
ruminants  and  swine,  characterized  by  hemorrhages  in  the  dif- 
ferent body  tissues  that  appear  as  small  red  spots  or  blotches. 


INFECTIOUS  DISEASES  295 

The  specific  cause  of  this  disease  is  tlio  Bacillus  septicemia 
hemorrhagica  (Fig.  101).  'riiis  hacillus  probably  enters  the 
body  tissues  by  way  of  the  lining  membrane  of  the  intestinal  and 
respiratory  tracts.  In  the  northern  States,  cattle  pasturing  on 
marsh  and  swr.mpy  pastures  are  more  often  affected  with  the  dis- 
ease in  the  late  summer  and  fall  than  at  other  seasons  of  the  year. 

The  drinking  of  contaminated  surface  water  that  collects 
in  muddy  pools  and  ponds  may  cause  the  disease.  Cattle  pas- 
turing in  stalk  fields  sometimes  become 
infected  in  this  way.  Dusty  sleeping 
quarters  and  small,  crowded,  muddy 
yards  seem  to  favor  the  development 
of  the  disease  in  hogs.  Exposure, 
insufficient  exercise  and  careless  feed- 
ing are  the  predisposing  factors. 

The  st/mploms  vary  according  to 
the  animal  and  organ,  or  organs  of 
the  body  an^ected  and  the  violence  oi  hemorrhauica. 

the  attack.  The  disease  may  be  acute  or  subacute.  The  brain 
and  its  membranes,  lungs  and  air-passages  and  intestines  may 
become  affected.  The  symptoms  may  be  classed  under  the  head 
of  nervous,  respiratory  and  intestinal  (Fig.  102),  and  they  may 
be  very  unsatisfactory  from  the  standpoint  of  diagnosis.  The 
history  and  post-mortem  lesions  are  of  most  value  in  the  recog- 
nition of  this  disease.  The  local  conditions,  the  loss  of  several 
animals  in  the  herd  and  the  finding  of  hemorrhagic  lesions  in  the 
different  body  tissues  may  enable  the  examiner  to  correctly  diag- 
nose the  disease.  It  is  very  advisable  in  order  to  confirm  the 
diagnosis  to  make  a  bacteriological  examination  of  the  tissues. 

The  acute  form  of  the  disease  is  very  fatal.  Animals  that 
have  the  subacute  form  usually  recover.  The  death-rate  is  be- 
tween five  and  fifteen  per  cent  of  the  herd.  The  mortality  is 
heavier  than  this  unless  prompt  preventive  measures  are  taken. 

Preventive  treatment  is  of  the  greatest  importance.  Cattle 
that  become  affected  when  running  on  pasture  should  be  moved, 


296 


INFECTIOUS  DISEASES 


or  in  case  a  part  of  the  pasture  is  swampy,  we  may  prevent 
further  loss  by  fencing  off  this  portion.  Drinking  pLaces  that  are 
convenient  and  free  from  hlth  should  be  provided.  Watering 
troughs  and  drinking  fountains  should  be  cleaned  and  disin- 
fected every  few  weeks.  For  this  purpose,  use  a  three  per  cent 
water  solution  of  a  cresol  disinfectant,  or  a  ten  per  cent  water 
solution  of  sulfate  of  iron.  Dusty  quarters  should  be  cleaned 
and  disinfected.     Dirt  floors  may  be  sprinkled  with  crude  oil. 


Fig.  102. — A  yearling  steer  affected  with  septicemia  hemorrhagica,  intestinal  form. 


All  of  the  animals  in  the  herd  sliould  be  vaccinated  with 
hemorrhagic  septicemia  bacterin.  Cattle  pasturing  in  a  field 
where  the  disease  has  been  known  to  occur  fiom  year  to  year, 
should  be  protected  by  vaccination. 

Anthrax,  Charbon. — This  is  an  acute  infectious  disease  af- 
fecting many  different  species  of  animals.  Anthrax  is  one  of 
the  oldest  animal  diseases,  and  early  in  the  history  of  the  race 
it  existed  as  a  plague  in  Egypt.  It  most  cc-xiimonly  affects  cattle, 
sheep  and  horses.  Man  contracts  the  disease  by  handling  wool 
and  hides  from  animals  that  have  died  of  anthrax,  and  by  acci- 


INFECTIOUS  DISEASES  297 

dental  inoculation  in  examining-  the  carcass  of  animals  lliat 
have  died  of  the  disease. 

Cause. — Anthrax  is  caused  by  a  rod-shaped,  spore-producing 
microorganism,  Bacillus  anUimcis  (i'ig.  lOo).  It  gains 
entrance  to  the  body  by  way  of  the  intestinal  tract,  lungs 
and  air-passages  and  the  skin.  The  bites  of  insects  play  an 
important  part  in  the  distribution  of  the  disease  in  some  lo- 
calities, but  the  most  common  method  of  infection  is  by 
way  of  the  digestive  tract,  through  eating  and  drinlcing  food 
and  water  contaminated  with  the  anthrax  germs.  The  spores 
of  the  B.  anthracis  are  very  resistant  to  changes  in  temperature 
and  drying.  They  may  live  for  years  in  rich,  moist  inundated 
soils,  lliver-bottom  and  swampy  hinds  that  have  become  in- 
fected with  discharges  from  the  bodies  of  animals  sick  with 
anthrax,  and  by  burying  the  car-  ^ 

casses  of  animals  that  have  died  of  '      ^'    *        *V 

this  disease,  retain  the  infection  for  •  »> 

many     years.     Anthrax     is     very    ^       ***» 
widely  distributed.  It  is  most  prev-  *'^  4^  .. 

alent  in  the  southern  portion  of  the  jt 

United  States,  especially  the  lower  y^       ^        .  \> 

portion  of  the  Mississippi  Valley.         *•'/  » 

The  sympto7ns  vary  171  dijferent       \^  -.^n*' 

cases,  depending  on  the  organs  af-  --v^. .    ^^^ 

fected,     and    the    virulence     and 

Fig.  103. — luicillu.^  anthracis. 

amount  of  virus  introduced.     The 

apoplectic  form  is  very  acute.  The  disease  sets  in  suddenly ;  the 
animal  trembles,  staggers,  falls  and  dies  in  a  convulsion.  Blood 
may  be  discharged  from  the  nose  and  with  the  urine  and  faeces. 

In  the  ahdominal  form,  abdominal  pain,  diarrhtca,  prolapse 
of  the  rectum,  bloating  and  doughy  swellings  in  the  region  of 
the  abdomen  occur. 

In  the  thoracic  form,  the  svanptoms  are  bloody  discharge  from 
the  nostrils,  salivation,  rapi<l,  ditlicult  ])reathing  and  swelling  in 
the  region  of  the  throat.  Local  or  skin  lesions  may  occur  in  con- 
junction with,  or  independent  of,  the  above  forms  of  disease. 


298  INFECTIOUS  DISEASES 

These  are  carbuncles  one  or  two  inches  in  diameter  that  are  hot 
and  tender  at  first,  but  later  become  gangrenous,  diffused  swellings. 

On  post-mortem  examination  the  blood  is  found  tarry  and 
dark,  and  bloody  exudates  may  be  found  in  the  abdominal  and 
thoracic  cavities.  The  spleen  is  soft  and  two  or  three  times 
larger  than  normal.  The  diagnosis  should  be  confirmed  by 
finding  the  B.  anthracis  in  the  blood  and  tissues.  The  death-rate 
is  very  high,  usually  about  seventy-five  per  cent. 

The  treatment  is  preventive.  Animals  should  be  kept  away 
from  lots  and  pastures  where  deaths  from  anthrax  have  been 
known  to  occur,  unless  immunized  against  the  disease.  Marshy, 
swampy  land  that  is  infected  with  the  germs  of  anthrax  should 
be  drained  and  cultivated. 

When  an  outbreak  of  the  disease  occurs,  all  of  the  animals 
should  be  vaccinated.  The  carcasses  of  the  animals  that  die 
should  be  cremated  at  or  near  the  place  where  they  die.  If 
hauled  or  dragged,  the  necessary  precautions  should  be  taken 
against  scattering  the  infectious  material  from  the  carcass,  and 
plenty  of  disinfectants  used.  Persons  attending  the  animals 
should  be  warned  against  opening  or  handling  the  carcass  without 
protecting  the  hands  with  rubber  gloves. 

Anthrax  vaccine  should  not  be  used  by  incompetent  persons. 

Ulcerative  Stomatitis.  (Ulcerative  Sore  Mouth.) — This  is 
an  infectious  disease  of  young  animals.  Pigs  from  a  few  days 
to  a  few  weeks  of  age  are  the  most  commonly  affected. 

The  specific  cause  of  ulcerative  sore  mouths  is  the  Bacillus 
necrophorus  (Pig.  104).  The  infectious  agent  is  distributed  by* 
the  udder  of  the  mother  becoming  soiled  with  filth  from  the 
stable  floor  and  yards,  and  by  affected  pigs  nursing  mothers  of 
healthy  litters.  Filth,  sharp  teeth  and  irritation  to  the  gums  from 
the  eruption  of  the  teeth  are  important  predisposing  factors. 

The  symptoms  are,  at  first,  an  inflammation  of  the  mucous 
membrane  lining  the  lips  and  cheeks  and  covering  the  gums. 
The  inflamed  parts  are  first  swollen  and  a  deep  red  color; 
later,  white  patches  form  and  the  part  sloughs,  leaving  a  deep 


INFECTIOUS  DISEASES  299 

ulcer.  As  ulceration  progresses,  difficulty  iu  nursing  increases 
until  finally  the  young  animal  is  unable  to  suckle.  If  ulceration 
of  the  mouth  is  extensive,  the  animal  may  be  feverish,  dull  and 
lose  flesh  rapidly.  Portions  of  the  lips,  gums  and  snout  may 
slough  off.     The  death-rate  in  pigs  is  very  high. 

The  preventive  treatment  consists  in  keeping  the  quarters 
and  yards  in  a  sanitary  condition,  and  using  all  possible  precau- 
tions against  the  introduction  of  the  disease  into  the  herd.  The 
diseased  young  and  mother  should  be  separated  fi-om  the  herd 
and  the  quarters  disinfected  daily.  The 
mouths  of  all  the  young  should  be  ex- 
amined daily  and  the  diseased  animals 
treated.  The  ulcers  should  be  scraped 
or  curetted  and  cauterized  with  lunar  I 
caustic,  and  the  mouth  washed  daily 
with  a  two  per  cent  water  solution  of 
a  cresol  disinfectant.  Dipping  pigs 
headforemost    into     a    water     solution 

.  ,  Fig.  104. — Bacillus  necrophorus. 

01    permanganate    oi    potassium    (one- 
half  teaspoonful  dissolved  in  a  gallon  of  water),  twice  daily, 
may  be  practised  if  the  herd  is  large. 

It  is  usually  most  economical  to  kill  the  badly  diseased 
animals,  as  they  usually  die  or  become  badly  stunted. 

Rabies,  Hydrophobia. — Rabies  is  an  infectious  disease  af- 
fecting the  nervous  system,  that  is  transmitted  by  the  bite  of  a 
rabid  animal  and  the  inoculation  of  the  wound  with  the  virus 
present  in  the  saliva.  It  is  commonly  considered  a  disease  of 
dogs,  but  because  of  the  disposition  of  rabid  dogs  to  bite  other 
animals,  rabies  is  common  in  domestic  animals  and  man. 

Eabies  is  widely  distributed,  being  most  prevalent  in  the 
temperate  zone,  and  where  the  population  is  most  dense.  It 
has  been  excluded  from  Australia,  Tasmania  and  New  Zealand 
by  a  rigid  inspection  and  quarantine  of  all  imported  dogs. 

The  specific  cause  of  rabies  is  probably  a  protozoan  para- 
site (the  Negri  bodies  present  in  nerve-cells,  Fig.  105).     The 


300 


INFECTIOUS  DISEASES 


germ  spreads  from  the  wounds  through  the  nerves  and  cen- 
tral nervous  system.  The  disease-producing  organisms  are 
present  in  great  numbers  in  the  nerve-tissue  and  saliva. 

The  period  of  incubation  varies  from  a  few  days  to  several 
months.     It  is  usually  from  ten  to  seventy  days. 

The  symptoms  diifer  in  the  different  species.  There  are  two 
forms  of  the  disease:  the  furious  and 
jr^A^^dumh.  The  former  is  more  common. 
.f.^-^-  In  the  dog,  the  symptoms  may  he 
divided  into  three  stages.  The  first,  or 
melancholy  stage,  usually  lasts  from 
twelve  to  forty-eight  hours.  The  ani- 
mal's behavior  is  altered  and  it  becomes 
sullen,  irritable  and  nervous.  Some- 
times it  is  friendly  and  inclined  to  lick 
the  hand  of  its  master.  An  inclination 
to  gnaw  or  swallow  indigestible  objects  is 
sometimes  noted.  Frequently  a  certain 
part  of  the  skin  is  rubbed  or  licked. 

The  second,  or  furious  stage,  may  last 
several  days.  Violent  nervous  or  rabid 
sjTuptoms  are  manifested,  and  the  dog  may  leave  home  and 
travel  long  distances.  The  animal  usually  shows  a  strong  inclina- 
tion to  bite.  It  may  move  about  snapping  at  imaginary  objects  in 
its  delirium,  and  may  bite  any  person  or  animal  with  which  it 
comes  in  contact.  The  Ijark  is  peculiar,  the  appetite  is  lost  and 
the  animal  becomes  weak  and  emaciated. 

In  the  third,  or  paralytic  stage,  the  dog  may  present  an  emaci- 
ated, dirty,  ragged  appearance.  The  lower  jaw  may  drop,  the 
tongue  hangs  from  the  lips  and  the  eyes  appear  sunken  and 
glassy.  >  Paralysis  of  the  hind  parts  may  be  present. 

In  the  dumb  form,  the  paralytic  s^Tuptoms  predominate  and 
the  disease  pursues  a  short  course.  Rabies  terminates  in  death 
in  from  four  to  ten  days. 


Fia.  105.- 


■^1 


-Negri  bodies  in  nerve- 
tissue. 


INFECTIOUS  DISEASES  301 

Furious  rabies  is  more  coiiinion  in  the  horse.  The  animal 
is  very  nervous,  restless  and  alert.  It  may  attack  other  animals 
in  a  vicious  manner,  kicking  and  biting  them.  The  animal 
does  not  seem  to  care  to  eat  or  drink,  and  usually  shows  violent 
nervous  symptoms,  such  as  biting  the  manger,  rearing  and  kicking 
when  confined  in  the  stable. 

Cattle  butt  with  the  horns  and  show  a  tendency  to  lick 
other  animals.  They  bellow  more  than  common  and  the  sexual 
desire  is  increased.  Parahi;ic  symptoms  are  manifested  early 
in  the  disease,  aud  the  animal  may  fall  when  moving  about. 
They  soon  present  a  gaunt,  emaciated  appearance. 

In  dogs  the  diagnosis  is  confirmed  by  a  microscopical  exam- 
ination of  the  vagus  ganglia  and  that  portion  of  the  brain  known 
as  Amnion's  horn,  and  the  finding  of  Xegri  bodies  in  the  nerve- 
cells.  In  case  a  person  is  bitten  by  a  dog,  the  animal  should  be 
confined  until  the  disease  is  well  advanced  and  killed  or  allowed 
to  die.  The  head  should  then  be  removed  and  forwarded  to 
the  State  laboratory,  or  wherever  such  examinations  are  made. 

Tlie  treatment  is  preventive.  Wherever  an  outbreak  of  rabies 
occurs  all  dogs  should  be  confined  on  the  owner's  premises  or 
muzzled.  All  dogs  running  at  large  without  muzzles  should  be 
promptly  killed.  A  heavy  tax  on  'dogs,  and  the  killing  of  all 
dogs  not  wearing  a  license  tag,  would  prevent  the  heavy  financial 
loss  resulting  from  rabies,  and  the  ravages  of  wandering  dogs  in 
the  United  States.  In  countries  where  the  muzzling  of  dogs  is 
enforced  during  the  entire  year,  rabies  is  a  rare  disease. 

Foot-and-mouth  Disease. — This  is  a  highly  contagious  and 
infectious  disease  of  cattle,  sheep,  goats  and  swine.  It  is  charac- 
terized by  the  eruption  of  vesicles  on  the  mucous  membrane  lining 
the  mouth,  the  lips,  between  and  above  the  claws  and  in  the  region 
of  the  udder  and  perineum.  Man  may  contract  the  disease  by 
caring  for  sick  animals ;  or  by  drinking  raw  milk  from  a  sick 
cow.    Babies  are  most  susceptible  to  infection  from  milk. 

Foot-and-mouth  disease  was  introduced  into  eastern  Europe 
from  the  steppes  of  Piiissia  and  Asia  near  the  end  of  the  eigh- 


302  INFECTIOUS  DISEASES 

teenth  century.  It  was  introduced  into  England  about  1839,  and 
in  1870  into  Canada  tliroui>li  the  importation  of  cattle  from 
England.  From  Canada  the  disease  spread  to  the  United 
States.  Very  few  animals  were  infected  during  the  1870  out- 
break, and  the  disease  was  quickly  stamped  out  in  both  countries. 

Europe  has  been  unable  to  eradicate  foot-and-mouth  dis- 
ease. The  different  outbreaks  that  occur  from  time  to  time  cause 
enormous  financial  loss.  In  the  United  States  outbreaks  of  the 
disease  have  occurred  in  the  following  years:  1870,  1884,  1902- 
'03,  1908  and  ]914-'15.  In  the  first  two  outbreaks  very  few 
cattle  contracted  the  disease,  and  the  infection  was  quickly 
stamped  out.  The  third  and  fourth  outbreaks  were  more  exten- 
sive, and  it  was  necessary  to  slaughter  several  thousand  cattle 
and  hogs  in  order  to  eradicate  the  disease.  The  first  four  out- 
breaks occurred  in  the  eastern  States,  and  the  disease  was  pre- 
vented from  spreading  to  the  principal  live-stock  centers  of  the 
country,  and  the  leading  stock-raising  States  by  slaughtering 
the  diseased  and  exposed  animals  and  by  county  and  State 
quarantines.  Early  in  the  1914-'15  outbreak,  the  disease  spread 
to  the  Chicago  Stock  Yards,  and  from  there,  through  shipments 
of  cattle,  to  the  princij)al  live-stock  sections  of  the  country.  The 
financial  loss  resulting  from  this  outbreak  has  amounted  to  several 
million  dollars.  The  Federal  and  State  authorities  have  always 
been  successful  in  stamping  out  the  disease  in  the  United  States. 

The  specific  cause  of  foot-and-mouth  disease  is  a  filterable 
virus  that  is  present  in  the  serum  from  the  vesicles,  the  saliva, 
milk,  and  various  body  secretions  and  excretions  from  the  sick 
animal.  In  the  early  stage  of  the  disease  it  is  present  in  the 
blood.  None  of  the  many  investigators  have  been  able  to  discover 
the  microorganism  that  produces  the  disease. 

Two  of  the  outbreaks  of  foot-and-mouth  disease  in  the  United 
States  originated  from  an  infected  vaccine  used  for  the  inocula- 
tion of  vaccine  heifers.  The  origin  of  the  1914-'15  outbreak  has 
not  been  discovered.    "When  introduced  into  a  country,  the  dis- 


INFECTIOUS  DISEASES 


303 


ease  spreads  rapidly,  tliroiigli  the  movement  of  live-stock  affected 
by  the  disease.  Animals  recently  recovered  may  infect  other 
animals.  Dogs,  birds,  people,  vehicles,  milk,  roughage,  grains 
and  other  material  from  an  infected  farm  may  spread  the  disease. 

The  period  of  incuhation  is  sliort.  Symptoms  of  disease  may 
be  manifested  in  from  one  to  six  days  following  exposure. 

The  first  symptoms  are  fever,  dulness,  trembling  and  loss  of 
appetite.     This  is  followed  by  vesicles  or  blisters  forming  on  the 


Fig.   106. — A  cow  affected  with  foot-and-mouth  disease.     Note  the  accumulation  of  saliva 
about  the  lips.     (From  report  of  the  Bureau  of  Animal  Industry.) 

mucous  membrane  of  the  mouth,  lips,  between  and  above  the 
claws  and  the  region  of  the  udder.  The  inflammation  of  the 
mouth  and  feet  may  be  very  painful.  Long  strings  of  saliva 
may  dribble  from  the  mouth  and  collect  about  the  lips  (Fig.  lOG). 
A  smacking  or  "  clucking  "  sound  is  produced  when  the  animal 
moves  its  jaws  and  lips.  The  severe  pain  resulting  from  the 
inflammation  of  the  mouth  and  feet,  and  the  difficulty  in  moving 
about  and  eating  and  drinking,  cause  the  animal  to  lose  flesh  and 
become  emaciated.     Milk  cows  may  go  dry. 

The  death-rate  is  not  heavy.     Some  writers  place  it  as  low 


304  INFECTIOUS  DISEASES 

as  two  or  three  per  cent.  Because  of  the  erosions  and  sloughing 
of  the  tissues  of  the  mouth,  feet  and  udder  it  becomes  necessary 
to  kill  manj  of  the  animals.  Young  animals  frequently  die  of 
inflammation  of  the  digestive  tract.  The  immunity  conferred 
by  an  attack  of  the  disease  is  not  permanent. 

The  most  economical  measures  of  prevention  and  control 
are  to  buy  and  slaughter  all  diseased  and  exposed  animals,  bury 
the  carcasses  in  quicklime,  disinfect  the  premises  '(Figs.  107,  108 


Fig.  107. — Federal  inspector  exaniining  the  mouth  of  a  suspected  case  of  foot-and-mouth 

disease. 

and  109)  and  enforce  a  district,  county  and  State  quarantine 
(Figs.  107,  108  and  109),  until  after  the  infection  has  died  out. 
This  statement  may  not  In^ld  true  of  methods  of  control  in 
countries  where  foot-and-mouth  disease  is  widely  distributed. 
Tetanus.  Lockjaw. — This  is  an  acute  infectious  disease 
that  is  cliaracterized  by  spasmodic  contractions  of  volantary 
muscles.  The  specific  germ  remains  at  the  point  of  infection,  and 
produces  toxins  that  cause  tetanic  contractions  of  the  muscles.  It 
commonly  affects  horses,  mules,  cattle,  sheep  and  swine.  The 
disease  is  most  common  in  warm,  temperate  climates. 


INFECTIOUS  DISEASES 


305 


Fio.  lOS. — Washing  coat  and  boots  with  disinfectant  after  inspecting  herd  for  foot-and- 
mouth  disease. 


Fin.  109. — Thein.sp(Mt(ir  fumigatinf:  cliithin«  witli  luinialdchyde.  This  is  an  additional 
precautionary  measure  for  the  purpose  of  {ireventing  any  possible  spread  of  foot-and-mouth 
disease  by  the  inspector. 

20 


306  INFECTIOUS  DISEASES 

The  specific  cause  is  a  pin-shaped  germ,  the  Bacillus  tetani 
(Fig.  110),  that  is  present  in  the  soil,  especially  those  that  are 
rich  and  well  manured.  The  germ  enters  the  body  by  way  of 
a  wound,  especially  punctured  wounds.  Infection  may  take 
place  through  some  wound  in  the  mucous  membrane  lining  the 
mouth,  or  other  parts  of  the  digestive  tract.  Infection  may 
follow  a  surgical  operation,  such  as  castration.  In  any  case, 
the  germ  requires  an  absence  of  air  (oxygen)  for  its  development. 
The  period  of  incubation  varies  from  one  to  two  weeks,  the 
length  of  time  depending  on  the  nearness  of  the  wound  to  a  large 
nerve  trunk  or  brain. 

The  first  symptom  observed  is  a  stiffness  of  the  muscles, 
especially  those  nearest  the  point  of  in- 
oculation or  wound.  The  muscles  of 
the  head,  neck,  back  and  loins  are  often 
affected  first,  and  when  pressed  upon 
with  the  fingers  feel  hard  and  rigid. 
The  disease  rapidly  extends,  producing 
spasms  of  other  muscles  of  the  body. 
In  breathing,  the  ribs  show  less  move- 
ment than  normal,  the  head  is  held  in 
Fig.  no.—BacUius  tetani.  qj^q  positiou  and  higher  than  usual, 
the  ears  are  stiff  or  pricked,  the  nostrils  dilated,  the  lips  rigid  or 
drawn  back  and  the  eyes  retracted,  causing  the  "  third  eyelid  " 
to  protrude  over  a  portion  of  the  eye  (Fig.  111).  In  most  cases 
the  muscles  of  mastication  and  swallowing  are  affected.  The 
animal  may  be  unable  to  open  its  mouth  and  swallows  with 
difiiculty.  AMien  standing,  the  limbs  are  spread  out  so  as  to 
increase  the  base  of  support,  and  in  acute  cases  about  to  ter- 
minate fatally,  the  pulse  is  quick  and  small  and  the  respiration 
shallow,  rapid  and  labored.  The  animal  sweats  profusely,  falls 
down  and  struggles  violently,  but  remains  conscious  to  the  end. 

In  the  subacute  form  (Fig.  112)  the  symptoms  are  mild, 
and  the  animal  may  be  able  to  move  about,  eat  and  drink  without 
very  great  effort. 


INFECTIOUS  DISEASES 


307 


Treatment  is  largely  preventive.  All  wounds  should  be  care- 
fully disinfected.  This  is  especially  advisable  in  punctured 
wounds  of  the  foot.  In  communities,  or  on  premises  where  teta- 
nus is  a  common  disease,  animals  that  have  punctured  or  open 
wounds  should  be  given  a  protective  dose  of  tetanus  antitoxin. 


Fig.  1 1 1  .—Head  of  horse  affected  wit  h  tetanus,  showing  "  third  eyeUd '  protruding  over  the  eye. 

The  curative  treatment  is  largely  good  care.  If  a  wound  is 
present,  it  should  be  thoroughly  disinfected.  The  animal  may 
be  supported  by  placing  it  in  a  sling.  A  comfortable  box-stall, 
where  the  animal  is  not  annoyed  by  noises  or  worried  by  other 
animals,  is  to  be  preferred.  A  fresh  pail  of  water  should  be 
given  the  animal  several  times  daily. 

The  course  of  the  disease  varies.     Death  may  occur  within 


308 


INFECTIOUS  DISEASES 


a  few  days,  or  the  disease  may  last  two  or  three  weeks.  Animals 
that  recover  from  tetanus  may  show  symptoms  of  the  disease 
for  several  weeks.  The  death-rate  is  highest  in  hot  climates  and 
during  the  summer  months. 

If  the  aiiiiiinl  can  ont.  it  i=;  not  advisable  to  feed  a  heavy 


Fig.   112. — A  subacute  oaoc  oi  icutnua. 

ration  of  roughage  or  grain.  A  very  light  diet  of  soft  food,  such 
as  chops  and  bran-mash,  prevents  constipation  and  encourages 
recovery.    Drugs  that  have  a  relaxing  effect  on  the  muscles  may 


be  given. 


Tetanus  antitoxin  may  be  given  in  large  doses. 


QUESTIONS 

1.  What  is  septicaemia  and  pyiFinia? 

2.  Wliat  is  liifmorrhagic  septicaemia?     Give  metliods  of  spreading  and  con- 

trolling this  disease. 

3.  Give  the  cause  of  anthrax  and  symptoms. 

4.  What  control  measures  are  recommended  in  anthrax? 

5.  What  is  ulcerative  sore  mouth?     Give  the  treatment. 

6.  Describe  the  symptoms  occurring  in  rabies,  and  state  the  control  measures 

recommended. 

7.  Name  the  species  of  animals  affected  by  foot-and-mouth  disease,  and  the 

countries  where  the  disease  is  prevalent. 

8.  Give  the  methods  of  distribution  and  control  of  foot-and-mouth  disease. 

9.  What  is  the  specific  cause  and  method  of  infection  in  tetanus?     Give  the 

treatment. 


CHAPTER  XXIX 


INFECTIOUS   DISEASES  OF  THE  HORSE 

Strangles.  Distemper. — This  is  an  acute  infectious  disease 
associated  with  a  catarrhal  condition  of  the  air-passages  and 
suppuration  of  the  lymphatic  glands  in  the  region  of  the  throat. 
Colts  are  the  most  susceptible  to  the  disease.  One  attack  renders 
the  animal  immune  against  a  second  attack  of  the  disease,  but  the 
immunity  is  not  always  permanent. 

The  specific  cause.  Streptococcus  equi  (Fig.  113),  was  dis- 
covered by  Schutz  in  1888.  Strangles  is  commonly  spread  by 
exposing  susceptible  animals  to  dis- 
eased animals,  either  by  direct  contact, 
or  by  exposing  them  to  the  infection  in 
the  stable  and  allowing  them  to  drink 
or  eat  food  from  watering  and  feeding 
troughs  on  premises  where  the  disease 
exists.  The  j)redisposing  causes  are 
cold  and  sudden  changes  in  the  weather. 
For  this  reason  the  disease  is  most 
prevalent  during  the  late  winter  and 
early  spring. 

The  period  of  incuhation  varies,  usually  from  four  to  eight 
days. 

The  symptoms  at  the  beginning  of  the  attack  are  a  feverish 
condition  and  partial  loss  of  appetite.  The  visible  mucous 
membranes  are  red  and  dry.  This  is  followed  by  watery  nasal 
secretions  that  become  heavy  and  purulent  within  a  few  days. 
The  inflammation  may  extend  to  the  larynx  and  pharynx. 

The  glands  in  the  region  of  the  jaw  become  hot,  swollen  and 
painful,  and  the  animal  may  be  unable  to  eat  or  drink.  The 
swelling  and  inflammation  of  the  throat,  and  the  heavy,  pus-like 

309 


Fig.   113. — Streptococcus  of 

strangles. 


310  INFECTIOUS  DISEASES 

secretions  that  accumulate  in  the  nasal  cavities,  cause  difficult 
respirations.  After  a  few  days  the  abscesses  usually  break,  and 
the  sjanptoms  are  less  severe.  If  the  abscesses  break  on  the 
inside  of  the  throat,  the  discharge  from  the  nostrils  is  increased. 

The  disease  may  be  accompanied  by  an  eruption  of  nodules, 
or  vesicles  on  the  skin,  or  nasal  mucous  membrane. 

In  severe  and  chronic  cases  multiple  abscesses  may  form. 
This  complication  is  indicated  by  emaciation  and  weakness. 
Such  cases  usually  terminate  in  death.  Severe  inflammation 
and  swelling  in  the  region  of  the  throat  may  terminate  in  strangu- 
lation and  death.     The  death-rate  is  from  one  to  three  per  cent. 

The  'preventive  treatment  consists  in  using  all  possible  pre- 
cautions to  prevent  the  exposure  of  susceptible  animals  and  prac- 
tising the  immunization  of  exposed  animals.  The  curative  treat- 
ment is  principally  careful  nursing.  Rest,  a  comfortable  stall, 
nourishing  feed  and  good  care  constitute  the  necessary  treatment 
for  the  average  case  of  distemper.  When  the  abscesses  become 
mature,  they  should  be  opened  and  washed  with  a  disinfectant. 
Steaming  the  animal  several  times  daily  relieves  difficult  breath- 
ing and  the  irritated  condition  of  the  mucous  membranes.  In 
case  the  abscesses  do  not  form  promptly  and  the  throat  is  badly 
swollen,  a  blistering  ointment  or  liniment  may  be  applied.  Bit- 
ter and  saline  tonics,  the  same  as  recommended  in  the  treatment 
of  indigestion,  may  be  given  with  the  feed. 

Influenza  (Catarrhal  or  Shipping  Fever). — This  is  a  well- 
knovm  acute  infectious  disease  of  solipeds.  It  is  characterized 
by  depression,  high  body  temperature  and  catarrhal  inflamma- 
tion of  the  respiratory  and  other  mucous  membranes. 

Several  epidemics  of  influenza  have  occurred  in  the  United 
States.  The  most  serious  epidemic  occurred  in  the  latter  part 
of  the  'TO's,  and  the  last  one  in  1900-'01.  Influenza  is  present 
in  the  principal  horse  centers  in  a  somewhat  attenuated  form. 

The  specific  cause  of  the  disease  has  never  been  determined. 
The  virus  is  present  in  the  expired  air,  nasal  secretions  and 


INFECTIOUS  DISEASES  OF  THE  HORSE  311 

excreta.  Close  proximity  to  a  diseased  animal  is  not  necessar;y 
in  order  to  contract  the  disease.  Stables  may  harbor  the  infec 
tion,  and  it  may  be  distributed  by  such  disease  carriers  as 
blankets,  harness,  clothing  of  the  attendant  and  dust. 

The  predisposing  causes  are  cold,  exposure  and  changes  in 
climate.  ^Vhen  the  disease  appears  in  a  country,  it  is  first  present 
in  the  large  cities,  and  from  there  it  is  scattered  to  the  outlying 
districts.  The  period  of  incubation  is  usually  from  four  to 
seven  days. 

The  early  symptoms  of  the  disease  are  a  high  fever,  marked 
depression  and  partial  or  entire  loss  of  appetite.  The  horse 
usually  stands  in  the  stall  with  the  head  down  and  appears 
sleepy.  The  visible  and  respiratory  mucous  membranes  are  in- 
flamed, the  respirations  are  quickened  and  the  animal  may 
cough.  The  eyes  are  frequently  affected,  the  lids  and  cornea 
showing  more  or  less  inflammation.  The  digestive  tract  may  be 
affected.  At  the  beginning,  colicky  pains  may  be  present  and 
later  constipation  and  diarrhoea.  SjTuptoms  of  a  serious  nervous 
disturbance  are  sometimes  manifested. 

The  limbs  usually  become  swollen  or  fllled.  This  disap- 
pears as  the  animal  begins  to  improve.  Pregnant  mares  may 
abort.     The  death-rate  is  low. 

The  treatment  required  for  the  sick  animals  is  largely  rest, 
a  light  diet  and  a  comfortable,  clean,  w^ell-ventilated  stall,  free 
from  draughts.  Windows  in  the  stall  should  be  darkened.  If 
the  stable  is  cold,  the  body  of  the  animal  should  be  covered  with 
a  blanket  and  the  limbs  bandaged.  Two  ounces  of  alcohol  and 
one  drachm  of  quinine  may  be  given  three  or  four  times  daily. 
Small  doses  of  raw  linseed  oil  may  be  given  if  necessary. 

Horses  that  are  exposed  to  cold,  wet  weather  or  worked  after 
becoming  sick,  frequently  suffer  from  pneumonia,  pericarditis, 
gastro-enteritis  and  other  diseases.  Such  complications  should 
be  given  prompt  treatment. 

It  is  very  advisable  to  give  a  protective  serum  to  horses  that 


312 


INFECTIOUS  DISEASES 


are  shipped  or  traiisjjorted  long  distances,  and  exposed  to  the 
disease  in  sale  or  transfer  stables. 

Glanders,  Farcy. — This  is  a  contagious  and  infectious  dis- 
ease of  solipeds  that  is  characterized  by  the  formation  of  nodules 
and  ulcers  on  the  skin,  nasal  mucous  membrane  and  lungs. 

Although  glanders  is  one  of  the  oldest  of  animal  diseases, 
it  was  not  until  1868  that  its  contagious  character  was  demon- 
strated. The  disease  is  widely  distributed.  It  became  more 
prevalent  in  the  United  States  after  the  Civil  War.  The  vigor- 
ous control  measures  practised  by  the  State  and  Federal  health 
officers  have  greatly  decreased  the  percentage  of  animals  affected 

with  glanders.  At  the  present  time 
the  disease  is  more  often  met  with  in 
the  large  cities  than  in  the  agricul- 
tural sections  of  the  country. 

The  specific  cause  of  glanders  is 
the  Bacillus  mallei  (Fig.  114).  This 
niierourganism  was  discovered  in  1882. 
It  is  present  in  the  discharges  from 
the  nasal  mucous  membrane  and  the 
ulcers.  These  discharges  may  become 
deposited  upon  the  feed  troughs, 
mangers,  stalls,  harness,  buckets,  watering  troughs,  drinking 
fountains  and  attendants'  hands  and  clothing.  Healthy  horses 
living  in  the  same  stable  Avith  the  glandered  animals  may 
escape  infection  for  months.  It  is  usually  the  diseased  animal's 
mate,  or  the  one  standing  in  an  adjoining  stall,  that  is  first 
affected.  Catarrhal  diseases  predispose  animals  to  glanders, 
as  the  normal  resistance  of  the  mucous  membranes  is  thereby 
reduced.  The  most  common  routes  by  which  the  germ  enters  the 
body  are  by  way  of  the  digestive  and  respiratory  tracts.  It 
may  enter  the  body  through  the  uninjured  mucous  membranes  of 
the  respiratory  tract  and  genital  organs,  or  through  wounds  of 
the  skin. 


Fig.    114. — Bacillus  mallei. 


INFECTIOUS  DISEASES  OF  THE  HORSE 


313 


The  period  of  inruJxdion  may  be  from  a  few  to  many  days. 

The  f>i/mpfoms  may  be  acute  or  chronic  in  nature.  The  acute 
form  pursues  a  rapid  course.  It  is  freciuently  seen  in  mules 
and  asses,  and  it  may  develop  from  the  subacute  or  chronic  form 
in  horses.  When  the  disease  is  acute,  the  animal  has  a  fever,  is 
stupid,  does  not  eat,  and  may  have  a  diarrhoea.  In  this  form  the 
hanpliatic  glands  suppurate,  the  animal  loses  flesh  rapidly 
and  dies  in  from  one  to  two  weeks. 

The  chronic  form  is  the  most  common.  It  develops  slowly 
and  lasts  for  years.  The  early  symptoms  of  the  disease  (chilling 
iind  fever)  usually  escape  notice.     The  first  visible  symptom  is  a 


Fig.  115. — Longitudinal  section  of  head  of  horse  having  glanders.    Ulcerated  portions  of 
nasal  mucous  membrane  indicated  by  A. 

nasal  discharge  of  a  dirty  white  color  from  one  or  both  nostrils. 
This  is  usually  scanty  at  first,  and  intermittent,  but  later  be- 
comes quite  abundant.  The  discharge  is  very  sticky,  and  adheres 
to  the  hair  and  skin.  The  most  frequent  seat  of  the  disease  is 
in  the  respiratory  organs,  lymph  glands  and  skin.  Xodulcs 
and  nlcers  appear  on  the  nasal  mucous  membrane  (Fig.  115), 
but  they  may  be  so  high  up  as  to  escape  notice.  The  ulcers  are 
very  characteristic  of  the  disease.  They  are  angry  looking,  with 
ragged,  raised  margins,  and  when  they  heal  leave  a  puckered 
scar.  The  submaxillary  glands  may  be  enlarged,  and  at  first 
more  or  less  hard  and  painful,  but  later  they  become  nodular  and 
adhere  to  the  jaw  or  skin.  Modules  and  ulcers  may  fonn  on  the 
skin  over  the  inferior  wall  of  the  abdomen  and  the  inside  of  the 


314  INFECTIOUS  DISEASES 

hind  limbs  and  are  known  as  "  farcy  buds."  Lymphatic  vessels 
near  these  buds  become  swollen  and  hard.  The  animal  loses 
flesh  rapidly,  does  not  withstand  hard  work,  and  the  limbs 
usually  swell. 

It  is  sometimes  difficult  to  diagnose  the  disease.  The  ulcers 
on  the  nasal  mucous  membranes  and  elsewhere  are  very  charac- 
teristic, and  when  present  enable  the  examiner  to  form  a  diag- 
nosis. In  cases  of  doubt,  a  bacteriological  examination  of  the 
nasal  discharge  may  be  made,  or  we  may  resort  to  one  or  several 
of  the  various  diagnostic  tests.  The  Mallein  test  is  quite 
commonly  used.     The  sterilized  products  of  a  culture  of  the 

B.  mallei  are  injected  beneath  the  skin 
of  the  suspected  animal.  This  causes 
a  rise  in  body  temperature  and  a  hot, 
characteristic  swelling  at  the  point  of 
I  injection  in  glandered  animals- 

Treatment  is  not  recommended  at 
the  present  time.     ISTearly  all  of  the 
States  have  laws  which  aim  to  stamp 
out   the    disease   wherever   found   by 
Fia.  na.— streptococcus  pyogenes   killing  all  afi"ected  animals,  and  thor- 
^""'^  oiigbly   disinfecting   the   stables,    har- 

ness and  everything  which  has  been  near  the  animal.  Dis- 
eased animals  should  be  carefully  isolated  until  slaughtered, 
and  all  animals  exposed  to  them  should  be  subsequently  tested 
for  glanders. 

Contagious  Pleuropneumonia  (Stable  Pneumonia). — This 
is  an  infectious  disease  of  solipeds  that  usually  results  in  a  fatal 
inflammation  of  the  lungs  and  pleural  membrane. 

Many  writers  have  described  this  disease  as  associated  with 
influenza,  but  it  is  frequently  seen  as  a  separate  disease,  usually 
involving  only  the  lungs  and  pleurae.  It  is  prevalent  in  several 
parts  of  the  United  States,  more  particularly  the  horse  centers 
or  large  markets,  where  it  appears  in  the  form  of  epidemics. 


INFECTIOUS  DISEASES  OF  THE  HORSE  315 

In  several  of  tlieso  localities  it  is  known  as  western  or  stable 
fever. 

The  specific  cause  is  not  de/inilehj  l-nown.  The  Slrcplo- 
coccus  pyogenes  equi  (Fig.  110)  is  very  commonly  present.  This 
germ  grows  in  the  diseased  tissues.  The  disease  is  spread  by 
direct  or  indirect  contact,  as  when  well  or  susceptible  animals 
are  placed  in  the  same  stable  with  an  animal  affected  with  the 
disease,  or  in  stalls  which  have  recently  held  diseased  animals. 

The  period  of  iricuhation  is  from  fonr  to  ten  days  following 
exposure. 

21ie  symptoms  are  tliose  commonly  seen  at  the  beginning 
of  an  attack  of  simple  pneumonia  and  pleurisy.  They  consist 
of  chills,  high  fever,  cough,  depression,  difficult  and  labored 
breathing  and  loss  of  appetite.  The  disease  usually  runs  a 
course  of  from  one  to  three  weeks.  The  death-rate  is  thirty  per 
cent  or  more. 

The  treatment  is  mainly  preventive.  Stables  where  horses 
having  pleuropneumonia  have  been  kept  should  be  cleaned  and 
disinfected  by  spraying  the  floors,  stalls  and  walls  with  a  four 
per  cent  water  solution  of  a  cresol  disinfectant.  It  is  advisable 
to  subject  all  newly-purchased  animals  to  a  short  quarantine 
period  before  allowing  them  to  mix  with  the  other  animals  in  the 
stable.     Exposed  animals  may  be  given  a  protective  serum. 

The  curative  treatment  is  the  same  as  recommended  for  the 
treatment  of  simple  pneumonia  and  pleurisy. 

QUESTIONS 

1.  \Miat  is  tlie  specific  cause  of  distemper?     Give  the  symptoms  and  treat- 

ment. 

2.  WTiat    are    the    different    methods    of    spreading    influenza?      Give    the 

symptoms  and  treatment. 

3.  Give  the  cause  and  methods  of  controlling  glanders. 

4.  Give  the  cause  and  treatment  of  contagious  pleuropneumonia. 


CHAPTER  XXX 

INFECTIOUS  DISEASES  OF  CATTLE 

Actinomycosis,  "  Lumpy  Jaw." — This  is  an  infectious  dis- 
ease that  is  characterized  by  the  formation  of  tumors  and  ab- 
scesses (Fig.  117),  and  the  destruction  of  the  infected  tissues. 
The  disease  is  common  in  cattle  and  usually  affects  the  bones 
and  soft  parts  of  the  head.     In  the  United  States,  where  the 


Fig.   117. — A  case  of  "lumpy  jaw  " 

disease  is  known  as  ''  lumpy  jaw,"  the  jawbone  is  commonly 
affected.  In  European  countries  the  disease  frequently  involves 
the  tongue,  and  the  term  "  wooden  tongue  "  is  applied  to  it. 
The  disease  may  affect  regions  of  the  body  other  than  the  head. 
Actinomycosis  of  the  lungs  sometim^es  occurs.  Swine  and  horses 
may  be  affected  by  this  disease. 
316 


INFECTIOUS  DISEASES  OF  CATTLE  317 

The  specific  cause  of  actinomycosis  is  commonly  known  as 
the  ray  fnngns  (Fig.  118).  This  fungus  grows  on  certain  plants, 
and  the  animal  usually  contracts  the  disease  by  eating  plants 
or  roughage  that  have  the  fungus  on  them.  Grasses  having 
awns  that  are  capable  of  woundirig  the  mucous  membrane  of 
the  mouth  and  penetrating  the  gums  are  most  apt  to  produce 
the  disease.  Young  cattle  that  are  replacing  and  erupting  their 
teeth  are  most  prone  to  "  lumpy  jaw."  (Conditions  that  favor 
bruising  of  the  jaw  and  external  wounds  favor  the  develoj^ment 
of  actinomycosis. 

The  fungus  grows  in  the  tissues,  causing  an  inflammatory 
reaction  and  destruction  of 
the  tissue.  The  ray  fungus 
can  be  seen  in  the  diseased 
tissue  or  the  pus  as  yellow- 
ish, sj)herical  bodies  about  the 
size  of  a  grain  of  sand.  Each 
of  these  bodies  is  formed  by 
a  large  number  of  club-like 
bodies  arranged  about  a  cen- 
tral mass  of  filaments,  il     W  "ft^'' 

The   local  symptoms   are  ir     1,0    -ru        t 

•J      L  Fig.  118, — The  ray  fungus. 

characteristic      (Fig.      117). 

The  tumor  may  involve  the  soft  tissues  of  the  head.  If  the  jaw- 
bone is  affected  the  tumor  feels  hard  and  cannot  be  moved  about. 
Sometimes  it  is  soft  and  filled  with  pus.  Tumors  of  long  stand- 
ing may  possess  uneven,  nodular  surfaces  and  fistulous  openings. 
When  the  tongue  is  affected,  it  is  swollen  and  painful,  and 
prehension  and  mastication  of  the  food  may  be  impossible. 
A\Tien  the  pharynx  is  the  seat  of  disease,  breathing  and  swallow- 
ing are  difficult  and  painful.  Actinomycosis  of  the  lungs  may 
present  the  appearance  of  a  chronic  pulmonary  affection.  If  the 
disease  involves  the  head  and  lungs,  the  animal  may  become 
unthrifty  and  emaciated.     In  doubtful  cases  a  microscopic  ex- 


318  INFECTIOUS  DISEASES 

amination  of  a  piece  of  the  tumor,  or  some  of  the  pus,  may  be 
necessary. 

The  treatment  is  surgical  and  medicinal.  Small,  external 
tumors  may  be  removed  by  an  operation.  Sometimes  an  incision 
is  made  into  the  diseased  tissue  and  a  caustic  preparation  intro- 
duced. 

The  most  desirable  method  of  treatment  is  the  administration 
of  large  doses  of  iodide  of  potassium  in  a  drench,  or  in  the 
drinking  water.  The  dose  is  from  one  to  three  drachms  daily 
for  a  period  of  seven  to  fourteen  days.  The  size  of  the  dose 
depends  on  the  size  of  the  animal  and  its  susceptibility  to  iodism. 
An  animal  weighing  1000  pounds  may  be  given  two  drachms. 
The  treatment  is  kept  up  until  the  symptoms  of  iodism  develop. 
The  condition  is  indicated  by  a  loss  of  appetite  and  a  catarrhal 
discharge  from  the  eyes  and  nostrils.  \Vhen  this  occurs,  the 
treatment  should  be  stopped,  and  the  animal  drenched  with  one- 
half  pound  of  Epsom  salts,  and  the  dose  repeated  after  three 
or  four  days.  After  an  interval  of  tw^o  weeks,  the  iodide  of 
potassium  treatment  should  be  repeated  if  the  growth  of  the 
tumor  is  not  checked. 

Emphysematous  Anthrax,  "  Black  Leg." — "  Black  leg " 
is  an  acute  infectious  disease  of  cattle  that  is  characterized  by 
lameness  and  superficial  swellings  in  the  region  of  the  shoulder, 
quarter  or  neck.  The  swellings  are  hot  and  painful  and  usually 
contain  gas. 

The  specific  cause  of  "  black  leg  "  is  a  rod-shaped,  spore- 
producing  germ,  the  bacillus  of  emphysematous  anthrax  (Fig. 
110).  This  germ  possesses  great  vitality,  and  may  live  indefi- 
nitely in  the  soil.  It  has  been  known  to  live  for  years  in  clay  and 
undrained  soils.  Young  animals  that  are  in  high  condition  are 
predisposed  to  the  disease. 

The  germ  enters  the  body  through  abrasions  in  the  skin  and 
mucous  membrane  of  the  mouth  and  intestines. 

"  Black  leg "  is  a  common  disease  of  young  cattle  in  all 


INFECTIOUS  DISEASES  OF  CATTLE  319 

sections  of  the  country  where  cattle-raising  is  engaged  in  exten- 
sively. Outbreaks  of  the  disease  are  most  prevalent  in  the  early 
spring  after  the  snow  has  melted,  and  in  the  late  summer  in 
localities  where  cattle  graze  over  the  dried-np  ponds  and  swampy 
places  in  the  pasture.  The  germs  of  black  leg  may  be  carried 
from  a  farm  where  the  disease  is  prevalent  to  non-infected  prem- 
ises by  surface  water.  The  opening  up  of  drainage  ditches 
through  stock-raising  communities  may  be  followed  by  out- 
breaks of  the  disease. 

The  symptoms  of  black  leg  develop  quickly  and  may  terminate 
fatally  in  a  few  hours.  These  are  gen- 
eral dulness,  stiffness,  prostration  and 
loss  of  appetite.  Lameness  is  a  promi- 
nent symptom.  The  animal  may  show  a 
swelling  in  the  regions  of  the  shoulder' 
and  hindquarters  or  on  other  parts  of 
the  body.  The  swelling  is  very  hot 
and  painful  at  first,  but  if  the  animal 
lives  for  a  time,  it  becomes  less  ten- 
der, crackles  when  pressed  on  and  the  Fig.  119.— Baciiiusof  emphysema- 

'  tou3  anthrax. 

skin    may    feel    cold     and    leathery. 

Fever  is  a  constant  symptom.     In  the  highly  acute  form  of  the 

disease  nervous  symptoms,  such  as  convulsions  and  coma,  occur. 

The  tissue  changes  in  the  region  of  the  swelling  are  charac- 
teristic. An  incision  into  the  swelling  shows  a  bloody,  dark 
exudate  and  the  surface  of  the  muscular  tissue  is  dark.  Frothy, 
bloody  liquid  escapes  from  the  mouth,  nose  and  anus. 

The  preventive  treatment  consists  in  thoroughly  draining 
pastures  and  yards  where  cattle  run.  This  measure  does  not 
insure  cattle  against  the  disease.  Cattle  that  die  of  "  black  leg  " 
should  be  cremated.  This  should  be  done  at  the  spot  where  the 
animal  dies.  If  the  carcass  is  moved  or  opened,  the  ground 
should  be  thoroughly  wet  wnth  a  four  per  cent  water  solution 
of  a  cresol  disinfectant  and  covered  with  lime. 


320 


INFECTIOUS  DISEASES 


Vaccination  of  the  exposed  or  susceptible  animals  should 
be  practised.  On  farms  where  the  disease  exists  it  may  be  neces- 
sary to  vaccinate  the  young  animals  (less  than  two  years  of  age) 
once  or  twice  every  year  in  order  to  prevent  the  disease.  Medic- 
inal treatment  is  unsatisfactory. 

Texas  or  Tick  Fever. — Tick  fever  is  an  infectious  disease 
of  cattle.  It  is  caused  by  an  animal  organism  that  is  present  in 
the  blood,  and  is  conveyed  from  the  animal  that  is  host  for  the 
tick  fever  parasite  to  the  non-infected  animal  by  a  tick  (Figs, 
120  and  121). 

Tick  fever  was  introduced  into  the  southern  portion  of  the 


Fig.  120. — Cattle  tick  (male).  Fig.   121. — Cattle  tick  (female). 

United  States  through  importation  of  cattle  by  the  Spaniards. 
Previous  to  the  establishing  of  a  definite  quarantine  line  between 
the  permanently  infected  and  the  non-infected  sections,  heavy 
losses  among  northern  cattle  resulted  through  driving  and  ship- 
ping southern  cattle  through  the  northern  States.  The  specific 
cause  and  the  part  taken  by  the  tick  in  its  distribution  were 
not  discovered  until  lS80-'90.  Smith  recognized  and  discovered 
the  specific  cause  of  the  disease,  and  Kilborn  and  Salmon  proved 
by  a  series  of  experiments  that  the  cattle  tick  was  respon- 
sible for  the  transmission  of  the  disease  from  animal  to  animal. 
Tlie  specific  cause  of  tick  fever  is  a  protozoan  parasite,  Piro- 


INFECTIOUS  DISEASES  OF  CATTLE  321 

plasma  higeminum  (Fig.  122).  It  is  present  in  the  blood  of 
cattle  that  are  affected  with  this  disease.  The  natural  method 
of  entrance  into  the  body  is  throngh  the  bite  of  the  cattle  tick. 
The  disease  may  be  transmitted  by  inoculating  blood  containing 
the  parasite  into  a  susceptible  animal.    - 

There  are  two  forms  of  the  disease,  the  acute  and  chronic. 

The  symptoms  of  the  acute  form  of  the  disease  are  a  high 
fever,  depression,  loss  of  appetite,  diarrhrra,  dark  or  bloody 
urine,  staggering  gait  and  delirium.  Death  may  occur  within 
a  few  days  from  the  time  the  first  symptoms  are  manifested. 

The  symptoms  of  the  chronic  form  of  the  disease  resemble 
the  acute  form,  but  are  more  mild. 
The  animal  is  unthrifty  and  loses 
flesh  rapidly.  The  bloodless  condition 
of  the  body  is  manifested  by  the  pale, 
visible  mucous  membrane.  Death 
seldom  occurs. 

The  most  characteristic  diseased 
changes  found  on  post-mortem  exami- 
nation occur  in  the  liver  and  spleen. 
The  liver  is  enlarged,   and  a  yellow-  Fig.   122.— Biood-ceiis  with  Pir^ 

"       '  ^  plasma  bigeminum  in  them. 

ish,  mahogany-brown  color.  The  gall- 
bladder is  filled  with  a  very  thick  bile.  The  spleen  may  be 
several  times  the  normal  size  and  dark  colored.  When  it  is  cut 
into,  the  pulpy  tissue  may  resemble  thick,  dark  blood.  The 
kidneys  are  pale  and  the  bladder  may  contain  dark  or  reddish- 
colored  urine. 

In  the  northern  States  and  outside  of  the  quarantined  area, 
the  direct  or  indirect  exposure  of  the  affected  cattle  to  southern 
cattle,  and  the  presence  of  the  cattle  tick,  Margarophus  anuu- 
latus,  are  sufficient  evidence  to  confirm  the  diagiiosis  of  this 
disease. 

The  prevention  and  control  depend  on  destruction  of  the 
cattle  tick.     In  the  early  history  of  the  disease,  shipping  and 
21 


322  INFECTIOUS  DISEASES 

driving  of  soiitliern  cattle  into  and  through  the  northern  States 
caused  outbreaks  of  tick  fever  and  heavy  losses  among  northern 
cattle.  This  finally  resulted  in  the  locating  of  the  infected 
district,  and  the  establishment  of  the  Texas-fever  quarantine 
line  in  1891  by  Dr.  D.  E.  Salmon. 

Previous  to  this  time  Kilborne  and  Salmon  proved  that  the 
cattle  tick  was  essential  to  the  spread  and  production  of  the 
disease.  A  further  study  of  the  life  history  of  the  tick  resulted 
in  the  discovery  that  it  could  not  mature  unless  it  became  a  para- 
site of  horses,  mules,  or  cattle.  This  has  led  to  the  eradication  of 
the  tick  in  certain  sections  of  the  South,  by  not  allowing  cattle 
access  to  a  pasture  or  lot  for  a  certain  period,  and  by  freeing 
the  animals  from  ticks  by  hand-picking,  dipping  and  smearing. 

The  immunization  of  cattle  that  are  shipped  into  an  infected 
district  for  breeding  purposes  is  often  practised.  Immunity  is 
obtained  by  introducing  the  P.  higeminum  into  the  blood,  either 
by  placing  a  few  virulent  young  ticks  upon  the  animal,  or  by 
repeated  inoculation  with  a  very  small  quantity  of  virulent  blood. 

QUESTIONS 

1.  Give  the  cause  and  treatment  of  actinomycosis. 

2.  Give  the  cause  and  treatment  of  emphysematous  anthrax. 

3.  Give  the  cause  of  tick  fever;  distribution  of  the  disease  and  methods  of 

control. 


CHAPTER  XXXI 
INFECTIOUS  DISEASES  OF  POULTRY 

Fowl  Cholera. — This  is  a  liiglily  infectious  disease  of  all 
species  of  poultry,  that  is  characterized  by  weakness,  depression 
and  yellowish  colored  excrement. 

The  specific  cause  of  fowl  cholera  is  the  Bacillus  avisepticus 
(Fig.  123).  This  microorganism  is  transmitted  to  the  healthy 
birds  by  the  feed,  or  water  becoming  contaminated  with  the  dis- 
charges from  the  diseased  birds.  According  to  Salmon,  the 
period  of  incubating  varies  from  four  to  twenty  days. 

llie  early  si/mptojns  are  a  falling  off  in  appetite,  high  fever, 
dulness,  diarrhcca  and  weakness.  The 
affected  bird  becomes  drowsy,  the  head 
is  drawn  toward  the  body,  and  it  may 
remain  asleep  for  long  periods  at  a 
time.  Salmon  states  that  the  general 
outline  of  the  sick  bird  becomes  spheri- 
cal or  ball-shaped. 

The  disease  is  usually  highly  fatal. 
In  the  acute  form  the  larger  portion 
of  the  flock  mav  die  off  within  a  week. 

"  _  Fig.   123. — Bacillus  aiisepticus. 

In  the  subacute  and  chronic  forms,  the 

birds  become  greatly  emaciated,  and  a  few  die  off  weekly  through 

a  period  of  a  month  or  longer. 

The  tissue  changes  occurring  in  the  disease  are  inflammation 
of  all  or  a  few  of  the  internal  organs.  Ward  states  that  the  most 
characteristic  lesion  of  fowl  cholera  is  the  severe  inflammation  of 
that  portion  of  the  small  intestine  nearest  to  the  gizzard.  Small 
hemorrhagic  spots  may  be  found  on  the  heart  and  other  organs. 

The  treatment  is  J>oth  preventive  and  curative.  The  pre- 
ventive  treatment    consists    in    quarantining   newly   purcha:?d 

323 


324  INFECTIOUS  DISEASES 

birds  until  we  are  satisfied  that  they  are  free  from  disease. 
The  occasional  disinfection  of  the  poultry  houses  and  runs  is 
highly  important.  Cleaning  the  poultry  house  by  removing  the 
floor,  roosts,  or  any  part  of  the  house  for  the  purpose  of  removing 
all  filth,  and  spraying  the  interior  with  a  three  per  cent  water 
solution  of  a  cresol  disinfectant,  should  be  practised.  Lime 
should  be  scattered  over  the  runs,  or  the  yards  immediately  about 
the  house.  The  above  preventive  measures  form  an  important 
part  of  the  care  and  management  of  the  flock.  The  carcasses  of 
the  dead  birds  should  be  burned.  It  is  advisable  to  kill  all  birds 
that  are  fatally  sick. 

All  of  the  flock  should  be  given  antiseptics  with  the  feed  and 
water.  Four  ounces  of  a  water  solution  of  copper  sulfate,  made 
by  dissolving  one-quarter  pound  of  this  drug  in  one  gallon  of 
hot  water,  may  be  added  to  each  gallon  of  drinking  water.  Fre- 
quent disinfection  of  the  drinking  fountains,  feeding  places  and 
houses  should  be  practised. 

Diseases  Resembling  Fowl  Cholera. — There  are  a  few  dis- 
eases, such  as  septicaemia,  limber  neck  and  infectious  enteritis, 
that  are  sometimes  mistaken  for  fowl  cholera.  These  diseases 
are  caused  by  different  microorganisms  that  may  be  found  in  the 
digestive  tract  and  air-passages  of  healthy  birds,  insanitary 
conditions  and  decomposed  feed,  especially  meat.  It  seems  that 
under  certain  conditions,  such  as  insanitary  quarters  and  birds 
that  are  low  in  constitutional  vigor  and  weakened  from  other 
causes,  certain  germs  may  become  disease-producers.  The 
death  rate  from  mixed  infections  is  very  heavy  in  poultry. 

The  symptoms  vary  in  the  different  cases.  The  disease  may 
be  highly  acute,  as  in  limber  neck,  or  chronic,  extending  over  a 
period  of  a  week  or  more.  Diarrha?a  is  not  a  prominent  symp- 
tom in  the  majority  of  cases. 

The  post-mortem  lesions  vary  from  a  hemorrhagic  to  a 
chronic  inflammation  of  the  different  body  organs  and  serous 
membranes. 


INFECTIOUS  DISEASES  OF  POULTRY  325 

The  treatment  is  preventive.  A  frequent  eleaninc;  and  dis- 
infecting of  the  poultry  house  and  surroundings,  avoiding  the 
feeding  of  spoiled  feed,  or  allowing  the  drinking  fountains  and 
feeding  places  to  become  filthy,  are  effective  preventive  measures. 
Sick  birds  should  be  either  isolated  and  quarantined,  or  de- 
stroyed. Antiseptics  may  be  given  with  the  feed  and  drinking 
water. 

Avian  Diphtheria,  Contagious  Epithelioma  (Roup). — This 
infectious  disease  of  poultry  is  especially  common  in  chickens. 
It  is  characterized  by  a  catarrhal  and  diphtheritic  inflammation 
of  the  mucous  membranes  of  the  head. 

The  specific  cause  of  roup  has  not  been  determined.  The 
disease-producing  germs  are  present  in  the  discharges  from  the 
nostrils,  eyes  and  mouth,  and  the  body  excretions  of  sick  birds. 
Birds  having  a  mild  form  of  roup,  or  that  have  recently  re- 
covered from  it,  are  common  carriers  of  the  disease.  The  dis- 
ease is  usually  introduced  into  the  flock  by  allowing  birds  ex- 
posed at  poultry  shows,  or  recently  purchased  breeding  stock 
from  an  infected  flock,  to  mix  with  the  healthy  birds. 

The  predisposing  causes  are  very  important  factors  in  the 
development  of  roup.  Cold,  damp,  draughty,  poorly  ventilated 
poultry  houses  cause  the  disease  to  spread  rapidly  and  become 
highly  acute. 

The  symptoms  differ  in  character  in  the  different  outbreaks 
of  the  disease.  Usually  the  first  symptoms  noticed  are  sneez- 
ing, dulness,  diminished  appetite  and  a  watery  discharge  from 
the  nostrils  and  eyes.  Later  the  eyelids  may  become  swollen  and 
the  nostrils  plugged  by  the  discharge  from  the  inflamed  mem- 
branes. If  the  mouth  is  examined  at  this  time,  an  accumulation 
of  mucus  and  patches  of  diphtheritic  or  false  membranes  are 
found.  In  the  acute  form  of  roup  the  false  membranes  and 
yellowish,  cheesy-like  material  accumulate  on  the  different 
mucous  membranes,  and  interfere  with  vision,  breathing  and 


326  INFECTIOUS  DISEASES 

digestion.  The  affected  bird  becomes  thin  and  weak.  The 
death  rate  is  very  high  in  this  form  of  the  disease. 

Chicken  pox  or  contagious  epithelioma  is  considered  by 
most  authors  a  form  of  roup.  It  is  characterized  by  nodules 
on  the  skin  along  the  base  of  the  comb  and  in  other  parts  of  the 
head. 

The  preventive  treatment  consists  in  quarantining  birds 
that  have  been  purchased  from  other  flocks,  and  that  have  been 
exhibited,  for  a  period  of  three  weeks.  A  careful  examination 
of  the  mouth  should  be  made.  If  a  catarrhal  discharge  from 
the  nostrils  and  false  membranes  is  present,  prompt  treatment 
should  be  used.  A  sick  bird  should  be  held  in  quarantine  for 
several  weeks  after  it  has  recovered,  and  receive  a  thorough 
washing  in  a  two  per  cent  water  solution  of  a  cresol  disinfectant 
before  allowing  it  to  mix  with  the  healthy  birds. 

The  medicinal  treatment  consists  in  removing  the  discharges 
from  the  nostrils  and  eyes  with  pledgets  of  absorbent  cotton 
that  are  soaked  with  a  four  per  cent  water  solution  of  boric 
acid.  Among  the  common  treatments  mentioned  are  boric  acid 
and  calomel,  equal  parts  by  weight,  blown  into  the  nostrils  and 
eyes  with  a  powder  blower.  Water  solutions  of  boric  acid  and 
potassium  permanganate,  and  hydrogen  peroxide  are  recom- 
mended. Liquid  preparations  are  applied  with  pledgets  of 
cotton,  oil  cans,  or  atomizers. 

Many  recoveries  can  be  obtained  with  careful  treatment.  It 
is  usually  most  economical  to  kill  the  severely  affected  birds. 
Many  poultrymen  dispose  of  the  entire  flock  as  soon  as  the  dis- 
ease makes  its  appearance,  and  clean  and  disinfect  the  premises 
before  restocking. 

Drs.  Mack  and  Records  report  very  satisfactory  results  in 
more  than  3,000  chickens  that  were  vaccinated  with  vaccine 
prepared  in  the  laboratory  from  scabs  and  diphtheritic  mem- 
branes collected  from  the  skin  and  mucous  membranes. 

Entero-hepatitis.  "Blackhead." — This  is  a  very  fatal  dis- 
ease of  youny;  turkeys.    Grown  turkevs  and  other  fowls  are  not  so 


INFECTIOUS  DISEASES  OF  POULTRY  327 

susceptible  to  the  disease.     It  is  characterized  by  an  inflamma- 
tiou  of  the  liver  and  intestines,  especially  the  ca-ca. 

The  specific  cause  is  a  protozoan  microorganism,  Ama'ha 
meleagridis.  Adnlt  fowls  and  turkeys  may  act  as  carriers  of  the 
germ,  and  the  young  turkeys  become  infected  at  an  early  period. 

The  symptoms  are  diminished  or  lost  appetite,  dulness, 
drooped  wings,  diarrha-a,  weakness  and  death.  When  the  dis- 
ease becomes  well  advanced,  the  head  and  comb  become  dark. 

The  course  of  the  disease  is  from  a  few  weeks  to  three 
months.     Very  few  of  the  young  turkeys  survive. 

The  treatment  is  almost  entirely  preventive.  The  same  pre- 
cautionary measures  for  the  prevention  of  the  introduction  of 
disease  into  the  lloek,  recommended  in  other  infectious  diseases, 
should  be  practised.  Turkeys  that  survive  should  be  disposed 
of.  As  chickens  may  harbor  the  disease-producing  germs,  we 
should  not  attempt  to  raise  turkeys  in  the  same  quarters  wuth 
them.  Eggs  should  be  obtained  from  disease-free  flocks.  Wip- 
ing the  eggs  with  a  cloth  wet  with  fifty  per  cent  alcohol  may  be 
practised.  The  same  recommendations  regarding  the  cleaning 
and  disinfecting  of  the  quarters  described  in  the  treatment  of 
fowl  cholera  should  be  practised. 

If  an  outbreak  of  the  disease  occurs  in  the  flock  all  of  the 
sick  birds  should  be  killed,  and  their  carcasses  cremated.  Mov- 
inc:  the  flock  to  fresh  runs  and  the  administration  of  intestinal 
antiseptics  are  the  only  eft'ective  lines  of  treatment. 

Avian  Tuberculosis. — Tuberculosis  of  poultry  is  a  serious 
disease  in  some  countries.  Poultry  usually  contract  tuberculosis 
by  contact  with  a  tubercular  bird,  and  not  from  other  domestic 
animals  and  man. 

The  symptoms  are  of  a  general  character,  such  as  emaciation, 
weakness,  wasting  of  muscles  and  lameness.  Tubercular 
growths  may  appear  on  the  surface  of  the  body. 

If  we  suspect  the  presence  of  the  disease,  it  is  advisable  to 
kill  one  of  the   sick  birds   and  make   a  careful   post-mortem 


328  INFECTIOUS  DISEASES 

examination.  The  finding  of  yellowish,  white,  cheesy  nodules 
or  masses  in  the  liver,  spleen,  intestines  and  mesenteries  ia 
strong  evidence  of  tnbercnlosis.  A  bacteriological  examination 
of  the  tissues  may  be  necessary  in  order  to  confirm  the  diagnosis. 
The  sa  ethods  of  treatment  as  recommended  in  tubercu- 

losis of  oti  lestic  animals  may  be  used  in  eliminating  the 

disease  from  the  premises  and  flock.  This  consists  in  killing 
and  cremating  all  birds  showing  visible  symptoms,  moving  the 
apparently  healthy  portion  of  the  flock  to  new  quarters  and 
wiping  the  eggs  with  alcohol.  The  old  quarters  should  be 
cleaned,  disinfected,  and  then  allowed  to  stand  empty  for  several 
months,  when  we  should  again  spray  with  a  disinfectant,  and 
scatter  lime  over  the  runs.  If  the  cleaning  and  disinfecting  have 
been  thorough,  we  may  safely  turn  young  or  healthy  birds  into 
the  old  quarters.  All  possible  precautions  against  carrying  the 
infection  to  the  healthy  flock  must  be  observed. 

QUESTIONS 

1.  Give  the  cause  and  treatment  for  fowl  cholera. 

2.  What  diseases  resemble  fowl  cholera?     Give  the  treatment. 

3.  Give  the  symptoms  and  treatment  for  roup. 

4.  Give  tlie  treatment  for  "  blackhead." 

5.  Give  the  treatment  for  Avian  tuberculosis. 

REFERENCE  BOOKS 

Pathology   and   Therapeutics   of   the   Diseases   of   Domestic   Animals,  Vol. 

1-11,  Hutyra  and  Marek. 
Veterinary  Medicine,  Vol.  1-V,  Law. 
General  Therapeutics  for  Veterinarians,  Frohner. 

Prevention  and  Treatment  of  tlie  Diseases  of  Domestic  Animals,  Winslow. 
Age  of  the  Domestic  Animals,  Huidekoper. 
Veterinary  Materia  Medica  and  Therapeutics,  Winslow. 
Veterinary  Anatomy,  Sisson. 

Chauveau's  Comparative  Anatomy  of  Domestic  Animals. 
Manual  of  Veterinary  Physiology,  Smith. 
Annual  Reports  of  Bureau  of  Animal  Industry,  from  1902  to  1911. 


INDEX 


Abortion,  73,  78 

accidental,  73,  78 

infectious,   73,   78 
Abscesses,  211,  212 
Acne,  121 

'Actinomycoses,  316,  318 
Administration  of  drugs,  17,  21 
Age  of  domestic  animals,  determin- 
ing the,   187,   195 
Anaemia  of  the  brain,  112,  114 
Animal   parasites,   248,   206 
Anthrax,  296,  298 

emphysematous,  318,  320 
Azoturia,  135,  137 

Blackhead,  326,  327 
"Black  leg,"  318,  320 
"  Bloating,"  33,  35 
Bog  spavin,   181,   182 
Bot-fly  of  cattle,  234,  235 
treatment  of,  236 

of  horse,  233,  234 

of  sheep,  235 

diseases,  symptoms  of,  235,  236 
Broken-knee,  150,  151 
Broken-wind,  102,  103 
Bronchitis,  96,  97 
Buck-knees,   151,  152 

Calculi,  63 

Caponizing,    226,   228 
Capped   elbow,    148,    150 

hock,  182,  183 
Care  of  the  mother  and  young,  80, 

82 
Castration,  222,  224 
Catarrh,  94,  95 
Catarrhal  fever,  310,  312 


Causes  of  disease,  4,  7 
exciting,  5 
predisposing,  5 
Charbon,  296,  298 
Chickenpox,    326 
Choking,  220,  222 
Cholera,  fowl,  323,  325 

hog,   269,  282 
Classification  of  disease,  3,  4 
Cold  in  the  head,  94,  96 
Colic,  40,  45 
Complications   following   castration. 

224,  226 
Congestion  of  the  brain,  112,  114 

of  the  lungs,  97,  98 
Conjunctivitis,   127,  128 
Contagious     pleuropneumonia,     314. 

315 
Contracted  quarters,  165,  167 

tendons,  155,  156 
Corns,   169,   170 
Crop,    distention    of   the,    51 
Curb,   183,   184 
Cystitis,  62,  63 

Dehorning  cattle,  219,  220 
Dental  diseases,   199,  200 
Depraved  appetite,  27,  28 
Determining  the  age  of  animals,  187 
189,  195,  196 
general  discussion,  187, 
188 
Diarrhoea,  47 

in  young  animals,  47,  50 
in  young  chickens,  52,  53,  54 
Disease,  general  discussion  of,  3,  4 
Diseases   of  the  circulatory  organs, 
104,  108 

329 


330 


INDEX 


Diseases   of  the   circulatory   organs, 
acute     lymphangitis, 
107,   108 
general  discussion,  104, 

105 
palpitation.  105,  100 
pericarditis,  106,  107 
of  the  digestive  system,   25,  54 
of  the  intestines,  39,  54 
of  the  mouth,  25,  27 
of  the  stomach,  28,  38 
of  the  digestive  tract  of  poultry, 
50,  54 
acute  and  chronic 
indigestion,    51, 
52 
of  the  crop,  51 
general  discussion, 

50,  51 
white  diarrhoea  of 
young    chickens, 
52,  53 
of  the  eye,  125,  130 

conjunctivitis,  127,  128 
examination  of  the  eye,  126, 

127 
general  discussion,  125,  126 
infectious     ophthalmia     of 

ruminants,  129,  130 
periodic      ophthalmia, 
"moonblindness,"  128, 129 
of  the  foot,  100,  173 

contracted     quarters,     165, 

167 
corns,  169,  170 
general  discussion,  160,  162 
laminitis,    "  foiinder,"    170, 

173 
navicular  disease,   163,  165 
sand-crack,  167,  169 
side-bones,  162,  163 
of  the  fore-limb,  147,  159 

capped   elbow,    "  shoe-boil," 
148,  150 


Diseases  of  the  fore-limb,  contracted 
tendons,    "knuckling 
over,"  155,  156 
distended     synovial     sacks, 
joint  sheaths  and  bursae, 
151 
inflammation  of  flexor  ten- 
dons,   153,    155 
of  sesamoid  bones,  155 
injuries  caused  by  interfer- 
ing, 156,  158 
injuries     to     the     knee, 
"  broken  knee,"   150,   151 
ring-bone,  158,  159 
splints,  152,  153 
sprains  and  injuries  of  the 

shoulder,  147,  148 
sprung  knees,  "  buck  knees," 
151,  152 
of  the  generative  organs,  65,  90 
abortion,  73,  78 
care  of  the  mother  and 

young,  80,  82 
general    discussion,    65 
genital    organs    of    fe- 
male, 65,  67 
organs  of  male,  67, 
68 
hygiene     of     pregnant 

animals,  71,  73 
leucorrhoea,  85,  86 
mammitis,  86,  87 
"  milk-fever  "    or   post- 
partum paralysis,  88, 
90 
physiology   of   parturi- 
tion, 78,  80 
retention   of   the    fetal 

membranes,  82,  85 
signs  of  pregnancy,  70, 

71 
sore  and  warty  teats,  87 
sterility,  impotency,  68, 
70 


INDEX 


331 


Diseases  of  the  hind  limb,  174,  184 
bog  spavin,  181,   182 
capped  hock,  182,  183 
curb,  1S3,  184 
fractures     of     the     ileum, 

"hipped,"    174,    17") 
luxation     of     the     patella, 

"  stifle  out,"  175,  17G 
spavin,  177,  181 
string-halt,  17(i,  177 
of  the  liver,  55,  57 
of    tlie    locomotory    apparatus, 
131,    137 
azoturia,  ha^moglobinu- 

ria,  135,  137 
general  discussion,  131, 

133 
rheumatism,  133,  135 
of  the  nervous  system,  109,  118 
congestion  and  anaemia 

of  brain,  112,  114 
general  discussion,  109, 

112 
meningo-cerebritis,  114, 

116 
paralysis    of    posterior 
portion  of  body,  IIG, 
118 
of    the    respiratory    organs,    91, 
103 
broken-wind,  "  lieaves," 

102,  103 
bronchitis,  96,  97 
catarrh,  94,  96 
congestion  of  the  lungs, 

97,  98 
general   discussion,   91, 

93 
pleurisy,  100,  102 
pneumonia,  98,   100 
ventilation,  93,  94 
of  the  skin.  119,  124 

acne,  "  summer  rash.''   121 
common  feed  rash,  123,  124 


Diseases  of  the  skin,  eczema,  122,  123 
falling     out    of     hair     and 

feathers,   120 
general  discussion.  111),  120 
herpes,  124 

urticaria,"  nettlerash," 
120,   121 
of   the   urinary   organs,   58,   64 
cystitis,  62,  63 
excessive  urination,  59, 

60 
general  discussion,   58, 

59 
necessity  of  examining 

the    urine,    59 
nephritis,   60,   62 
retention  of  the  urine^ 
63,  64 
Diphtheria,  avian,  325,  326 
Distemper,  309,  310 
Dose,  size  of  the,  21 
Drugs,  administration  of,  17,  21 

Eczema,   122,   123 
Emphysematous  anthrax,  318,  320 
Enteritis,  45,  47 
Entero-hepatitis,  326,  327 
Eye,  examination  of,  126,  127 
inflammation  of,  127,  128 

Falling  out  of  liair  and  featliers.  120 

Farcy,  312,  314 

Feed  rash,   123.   124 

Fetal  membranes,  retention  of,  82,  85 

Fistulous  withers,  212,  213 

Flexor     tendons,     inflammation     of, 

153,  155 
Foot-and-niontli  disease,  301,  304 
Foreign    bodies    in    the    stomach    of 

ruminants,  37,  38 
"Founder."  170,  173 
Fowl  cholera,  323,  324 

diseases     resembling,      324, 
325 


332 


INDEX 


Fractures,  214,  216 

of  the  ileum,  174,  175 

(jJapes  in  birds,  265,  266 
Genital  organs  of  female,  65,  67 

of  male,  67,  68 
Glanders,  312,  314 

Haemoglobinuria,  135,  137 

Harness  injuries,  216,  218 

Heatstroke,   114 

Heaves,   102,   103 

Hemorrhagic  septicemia,  294,  296 

Hernia,  inguinal,  225,  226 

Herpes,    124 

"Hipped,"    174,    175 

Hog-cholera,  269,  282 

accessory  causes,  269,  272 
anti-hog-cholera  serum,  279,  282 
care  of  diseased  herd,  277,  278 
differential   diagnosis,   274,  275 
disinfection  of  yards,  279 
disposal  of  dead  hogs,  279 
lesions,  275,  276 
period  of  incubation,  272 
preventive  measures,  276,  277 
specific  cause,  269 
symptoms,  272,  274 
vaccination  of  hogs,  280,  282 

Hydrophobia,  209,  301 

Hygiene  of  pregnant  animals,  71,  73 

Impaction  of  the  omasum,  36,  37 
Impotency,  68,  70 

Indigestion,  acute  intestinal,  of  soli- 
peds,   40,   45 
in  poultry,  52 
of   the   stomacli    of    ruminants, 

acute,  33,  38 
of  the  stomach  of  solipeds,  acute, 
30,  33 
Infectious  ophthalmia  of  ruminants, 
129, 130 


Inflammation,  203,  205 

of  the  bladder,  62,  63 

of  the  brain  and  its  coverings, 
114,  116 

of  the  bronchial  tubes,  96,  97 

of  the  eye,  127,  128 

of  the  intestines,  45  47 

of  the  kidneys,  60,  62 

of  the  lungs,  98,  100 

of  the  pericardium,  106,  107 

of  the  pleura,  100,  102 

of  the  stomach  of  swine,  38 

of  the  udder,  86,  87 
Influenza,  310,  312 
Inguinal  hernia,  225,  226 
Interfering,  injuries  caused  by,  156, 

158 
Intestinal  parasites  of  hogs,  259,  261 

worms  of  cattle,  256,  257 
of  solipeds,  255,  256 
Irregularities  of  the  teetli,  196,  200 

Kidney  worm  of  liogs,  tlie,  204 
Knee,  injuries  to  the,  150,  151 
Knuckling  over,  155,  156 

Laminitis,  170,  173 
Lantern-jaw,  196,  197 
Leucorrhuea,  85,  86 
Lice,  236,  241 

symptoms  of,  237,  239 
Liver,  diseases  of,  55,  57 
Liver  fluke,  248,  251 
Lockjaw.  304,  308 
Lousiness,  treatment  of,  239,  241 
"  Lumpy  jaw,"  316,  318 
Luxation    of   the    patella,    175,    176 
Lymphangitis,  acute,  107,  108 

Mammitis,  86,  87 
Mange  in  horses,  244 

treatment  of,  244,  246 
Meningo-cerebritis,  114,  116 
Milk-fever,  88,  90 


INDEX 


333 


Mites,  diseases  of  poultry  caused  by, 

246,  247 
treatment    of    poultry    diseases 

caused  by,  247 
'•  Moonblindness,"   128,   129 
Mouth,  diseases  of  the,  25,  27 

Navicular  disease,   163,   165 
Nephritis,  60,  62 
Nettlerash,  120,  121 

(Estridae,  233,  237 
Omasiun,  impaction,  36,  37 
Ophthalmia,     infectious,     of     rumi- 
nants, 129,  130 
periodic,  128,  129 
Ovariotomy.  228,  230 
Overloading  of  the  riimen,  35,  36 

Palpitation,  105,  106 

Paralysis  of  the  posterior  portion  of 
the  body,  116,  118 

Parasitic  insects  and  mites,  233,  247 

diseases      of      poultry 

caused  by  mites,  246, 

247 

lice,   236,   241 

the  parasitic  flies,  233, 

236 
scabies,  242,  246 
the  sheep-tick,  241,  242 

Parrot-mouth,  196.  197 

Parturition,  physiology'  of,  78,  80 

Pericarditis,  106,  107 

Periodic  ophthalmia,   128,   129 

Pleurisy,   100,   102 

Pneumonia,  98,   100 

Poll   evil,   212,  213 

Post-partum  paralysis,  88,  90 

Pregnancy,   signs  of,   70,   71 

Pya'mia,  293,  294 

Quarter-crack,   167,   169 


Rabies,  299,  301 

Retention  of  the  fetal  membranes,  82, 
85 
of  the  urine,  63,  64 
Rheumatism,  133,  135 
Ring-bone,  158,  159 
Round-worms,  253,  255 
Roup,  325,  326 

Rumen,  overloading  of,  35,  36 
"  Rupture,"  inguinal,  225,  226 
Rupture  of  the  stomach  of  solipeds. 
32 

Sand-crack,  167,  169 
Scab,  242,   246 

treatment  of,  244,  246 
Scabies,  242,  246 
Schirrous  cords,  226 
Scissor-mouth,  196,  197 
Scratches,    122 
Septicemia  293,  294 

hemorrhagic,  294,  296 
Serum,  anti-hog-cholera,  279,  280 
Sesamoid  bones,  inflammation  of,  155 
Sharp  teeth,  197 
Sheath,  inflammation  of  the,  04 
Sheep  tick,  the,  241,  242 
Shipping  fever,  310,  312 
Shoe-boil,  148,  150 
Shoulder  sprains,  147,   148 
Side-bones,  162,  163 
Signs  of  pregnancy,  70,  71 
Size  of  the  dose,  21 
Smooth-mouth,  198 
Sore  mouth,  ulcerative,  298,  299 
Sore  and  warty  teats,  87 
Spavin,  177,  181 

bog,  181,  182 
Spaying,  228.  230 
Sprains  and  injuries  to  the  region  of 

the  shoulder,  147,  148 
Sprung  knees,  151,  152 
Stable  pneumonia,  314,  315 
Sterilitv,  68,  70 


334 


INDEX 


Stifle    out,    175,    177 
Stomach,  diseases  of  the,  28,  38 
of    the    hog,    30 
of  the  horse,  28,  29 
of  the  ruminant,  29,  30 
worms  of  sheep,  257,  259 
Stomatitis,  non-infectious  or  simple, 
26,  27 
ulcerative,   298,   299 
Strangles,  309,  310 
String-halt,  176,  177 
Structure    of    the    limbs    of    horses, 
138,    142 
arm,  138 
cannon,  139 
digit,  140 
forearm,   139 
general  discussion,  138 
hock,    141,    142 
knee,   139 
leg,  141 
pelvis,  140 
shoulder,  138 
thigh,  141 
■'  Summer  rash,"  121 
Sunstroke,   114 
Surgical    operations,    common,    219, 

230 
Symptoms,  general,  8,  15 

behavior  of  animal,  15 
body  excretions,   15 
body  temperature,  13,  14 
pulse,  9,  11 
respirations,  11,  13 
surface  of  body,  14,  15 
visible  mucous  membranes, 
14 
Synovial    sacks,    joint    sheaths    and 
bursse,  distended,  157 

Tapeworms,  251,  252 
Tetanus,  304,  308 
Texas  fever,  320,  322 
Thorn-headed  worm,  252,  253 


Thorough  pin,  181 

Throat,  inflammation  of  the,  95 

Tick  fever,  320,  322 

Treatment,  medicinal,  17 
preventive,   16,    17 

Tuberculin  test,  289,  291 

Tuberculosis,  283,  292 
avian,   327,   328 
control  of,  291,  292 
direct  cause,  285 
history,  233,  284 
introduction   of,   into  herd,  285 
post-mortem  lesions,  287,  289 
predisposing  cause,  285 
prevalence  of  the  disease,  284 
symptoms,  285,  287 
tuberculin  test,  289,  291 

Tympanitis,  33,   35 

Ulcerative  stomatitis,  298,  299     : 
Unsoundnesses   and    blemishes,    143, 
146 
examination,  144,  146 
general  discussion,  143 
recognition  of  disease,  143 
Urination,  excessive,  59,  60 
Urine,  necessity  of  examination  of,  59 

retention  of,  63,  64 
Urticaria,  120,  121 

Vaccination  of  hogs,  280,  282 

Ventilation,   93,   94 

Verminous  bronchitis  in  calves,  202 

in  hogs,  263,  264 

and    pneumonia    of    sheep, 
262,  263 

Warty  and  sore  teats,  87 

White  scours  in  young  animals,  47, 

50 
Worms    of    the    digestive    tract    of 

poultry,  264,  265 
Wound,  healing,  208,  209 

treatment,  209,  211 
Wounds,  205,  211 


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